Traders to the Death

Question

You are a foreign trader, hoping to make a profit. There are 5 goods people wish to trade: Apricots, Boars, Canaries, Daffodils, and Earwigs. Starting in the winter, you need to decide what to produce. Then, in the fall, you travel and spend your days trading for a profit.

Gameplay

You start the game with 10 of each product in storage. Each year, you will consume 2 of each product.

At the beginning of the game, you receive a list of 5 products, along with the amount you will be able to produce each year (ex:5-A,6-B,3-C,12-D,4-E). You then will return a letter A through E deciding what to produce.

Then, in the fall time you will bring your products (including those in storage) to the market. You have 50 turns to trade.

You must decide if you want to Purchase, Sell, or Leave the market. The buyers will then be paired up randomly with the sellers. If a group has extra, the random extras will miss out this turn. If a trader is skipped, they will receive S, otherwise, T. The seller must decide what he wants to sell, and amount (ex:3-A), and then what he would accept (ex:5-B,2-D,1-E) (The values are any of not all of). The buyer will then be told what product the seller is selling, then the products the seller will take for it, and he can choose a product to trade for it (ex: D or X for nothing).

After all trades are over, or after you have left the market, you will consume 2 of each product, and the year starts over. If you have less than 2 of any 1 product, you will die (and passed Q).

Your score will be the number of years you last, and after 50 games, your scores will be averaged for your total score.

Optional moves

At any time you can return G to query your goods

At any time you can return N to query the number of new products in your inventory (produced by any player in the past year, and new products will be traded before old products)

At any time you can return T for the current Turn phrase: Produce, Market, or Trading

During a trade, you can query I for an identifier unique to the player you are trading with.

During a trade, you can return M to query the number of people trading

How to code it:

You may use any standard language, and must include a command.txt which is the command to run your program.

The general flow of your program should be:

Get productivity
While alive:
    Output product you want to produce
    While in trading:
        Output whether you want to purchase or sell
        Get whether or not you were skipped.  If not skipped:
            If purchasing:
                print product you offer, and products you will accept
            Else:
                Get product offered, products being accepted, and choose the product you will give

I have a tester program here. To use it, create a folder in the bots folder with your bot's name. Add a command.txt, your program, and anything else your program needs. I will be adding submissions as they come in. If you don't want to install the languages required to run some or all of them, you just need to delete the command.txt in the bot's folder.

Inner Workings

There will be 5 bots for each program submitted. The ID will be different for bots of the same type.

I will call the amount a person can produce a given product the productivity. Each product will be given a base productivity, where all of the base productivity will add up to 30. One of the scores will be ensured to be at most 3, and all will be at least 2.

Then, each player's productivity will vary from the base productivity (One value will vary by +2, another +1, then +0, -1, and the remaining value will vary by -2).

The base productivity will change from game to game.

Scores:

seer:                10.128 years
level_headed_trader: 8.196 years
introvert:           6.856 years
random_ando:         5.408 years
hoarder_trader:      4.12 years
ratio_trader:        3.532 years
scared_trader:       3.056 years

Answer 1

Seer

This program predicts the future, and he chooses the trades which will increase his expected lifespan.

This isn't completely finished, because he only knows how to buy things but not sell things, so expect an update in the future. Regardless, I believe that he will be competitive as-is.

$| = 1;
@names = ('A','B','C','D','E');
@counts = (12,12,12,12,12);
%names = ('A',0,'B',1,'C',2,'D',3,'E',4);

sub predict{
 local @a = @_;
 local $minval = 1000;
 local $minloc = 0;
 for(0..~~@a-1){
  if($a[$_]<$minval){
   $minloc = $_;
   $minval = $a[$_]
  }
  $a[$_]-=2;
 }
 if($minval <= 1){return (0,@a)}
 if($minval == 100){return (10000,@a)}
 $a[$minloc] += $productivity[$minloc];
 local @b = predict(@a);
 @b[0]++;
 return @b;
}

sub choice{
 local @a = @_;
 local $minloc = 0;
 local $minval = 1000;
 for(0..~~@a-1){
  if($a[$_]<$minval){
   $minloc = $_;
   $minval = $a[$_]
  }
 }
 return $minloc;
}


$productivity = <>;
@productivity = split(',',$productivity);

#@c = predict(@counts);
#print "@c\n";
$alive = 1;
while($alive){
 for(0..4){
  $counts[$_] -= 2;
 }
 $choice = choice(@counts);
 print "$names[$choice]\n";
 $counts[$choice] += $productivity[$choice];
 for(1..50){
  print "P\n";
  chomp($in = <>);
  if($in eq "T"){
   chomp($forsale = <>);
   ($quantity,$type) = split("-",$forsale);
   $type = $names{$type};
   #print "$quantity, $type\n";
   chomp($in = <>);
   @options = split(",",$in);
   @baseline = predict(@counts);
   $lifespan = shift @baseline;
   $basescore = $lifespan * 1000;
   @bestcounts = @counts;
   for(0..4){
    $basescore -= 10**(-1 * $baseline[$_]);
   }
   #print "Base: $basescore\n";
   @hypo = ();
   $bestscore = $basescore;
   $choice = "X";
   for(0..$#options){$curchoice = $_;
    ($cost,$ctype) = split("-",$options[$curchoice]);
    $ctype = $names{$ctype};
    @tempcounts = @counts;
    $tempcounts[$type] += $quantity;
    $tempcounts[$ctype] -= $cost;
    @curhypo = predict(@tempcounts);
    @hypo[$curchoice] = [@curhypo];
    #print "@curhypo\n";
    $lifespan = shift @curhypo;
    $score = $lifespan * 1000;
    for(0..4){
     $score -= 10**(-1 * $curhypo[$_]);
    }
    #print"$score\n";
    if($score > $bestscore){
     $bestscore = $score;
     $choice = $names[$ctype];
     @bestcounts = @tempcounts;
    }
   }
   print "$choice\n";
   @counts = @bestcounts;
  }
  #print"@counts\n";
  #@c = predict(@counts);
  #print "@c\n";
 }
}

I run this program like so:

perl seer.plx

Answer 2

Level-headed Trader

This bot tries to make his quantities as equal as possible

command.txt

python leveller.py

leveller.py

import sys

def current_goods():
    print "G"
    return parse_goods(readline())

def parse_goods(good_string):
    return dict([(a, int(b))
                 for a, b in [product.split("-")
                              for product in good_string.split(",")]])

def get_minimum(goods):
    cur_min = 200
    min_good = "X"
    for good, amount in goods.items():
        if amount < cur_min:
            min_good = good
            cur_min = amount
    return min_good

def get_maximum(goods):
    cur_max = -1
    max_good = "X"
    for good, amount in goods.items():
        if amount > cur_max:
            max_good = good
            cur_max = amount
    return max_good

def add_goods(x, y):
    return {k: int(x.get(k, 0)) + int(y.get(k, 0)) for k in set(x) | set(y)}

def readline():
    line = sys.stdin.readline().strip()
    if line == 'Q' or not line:
        exit()
    return line

def output_goods(goods):
    print ",".join([good+"-"+str(amount) for good, amount in goods.items()])

def output_good(good, amount):
    print good+"-"+str(amount)

def current_turn_is(turn):
    print "T"
    return readline() == turn

turns = MARKET, PRODUCE, TRADING, SKIPPED = "M", "P", "T", "S"
market_options = PURCHASE, SELL = "P", "S"
items = APRICOTS, BOARS, CANARIES, DAFFODILS, EARWIGS, NOTHING = "A", "B", "C", "D", "E", "X"

productivity = parse_goods(readline())
while True:
    product_to_produce = get_minimum(current_goods())
    print product_to_produce
    while current_turn_is(MARKET):
        print SELL
        if readline() != SKIPPED:
            maximum = get_maximum(current_goods())
            goods = {"A": 1, "B": 1, "C": 1, "D": 1, "E": 1}
            del goods[maximum]
            output_good(maximum, 1)
            output_goods(goods)

Answer 3

Scared Trader

This trader avoids getting low numbers

command.txt

python scared.py

scared.py

import sys

def current_goods():
    print "G"
    return parse_goods(readline())

def parse_goods(good_string):
    return dict([(a, int(b))
                 for a, b in [product.split("-")
                              for product in good_string.split(",")]])

def get_minimum(goods):
    cur_min = 200
    min_good = "X"
    for good, amount in goods.items():
        if amount < cur_min:
            min_good = good
            cur_min = amount
    return min_good

def get_maximum(goods):
    cur_max = -1
    max_good = "X"
    for good, amount in goods.items():
        if amount > cur_max:
            max_good = good
            cur_max = amount
    return max_good

def add_goods(x, y):
    return {k: int(x.get(k, 0)) + int(y.get(k, 0)) for k in set(x) | set(y)}

def readline():
    line = sys.stdin.readline().strip()
    if line == 'Q' or not line:
        exit()
    return line

def output_goods(goods):
    print ",".join([good+"-"+str(amount) for good, amount in goods.items()])

def output_good(good, amount):
    print good+"-"+str(amount)

def current_turn_is(turn):
    print "T"
    return readline() == turn

turns = MARKET, PRODUCE, TRADING, SKIPPED = "M", "P", "T", "S"
market_options = PURCHASE, SELL = "P", "S"
items = APRICOTS, BOARS, CANARIES, DAFFODILS, EARWIGS, NOTHING = "A", "B", "C", "D", "E", "X"

productivity = parse_goods(readline())
while True:
    current = current_goods()
    min_product = get_minimum(current)
    min_amount = current[min_product]
    product_to_produce = min_product if min_amount < 4 else get_minimum(productivity)
    print product_to_produce
    while current_turn_is(MARKET):
        print SELL
        if readline() != SKIPPED:
            current = current_goods()
            maximum = get_maximum(current)
            minimum = get_minimum(current)
            to_offer = {maximum: max(productivity[maximum]/productivity[minimum], 1)}
            output_good(minimum, 1)
            output_goods(goods=to_offer)

Answer 4

Hoarder Trader

This trader tries to get as many products as possible.

command.txt

python hoarder.py

hoarder.py

import sys

def current_goods():
    print "G"
    return parse_goods(readline())

def parse_goods(good_string):
    try:
        return dict([(a, int(b))
                     for a, b in [product.split("-")
                                  for product in good_string.split(",")]])
    except:
        raise IOError(good_string)

def get_minimum(goods):
    cur_min = 200
    min_good = "X"
    for good, amount in goods.items():
        if amount < cur_min:
            min_good = good
            cur_min = amount
    return min_good

def get_maximum(goods):
    cur_max = -1
    max_good = "X"
    for good, amount in goods.items():
        if amount > cur_max:
            max_good = good
            cur_max = amount
    return max_good

def add_goods(x, y):
    return {k: int(x.get(k, 0)) + int(y.get(k, 0)) for k in set(x) | set(y)}

def readline():
    line = sys.stdin.readline().strip()
    if line == 'Q' or not line:
        exit()
    return line

def output_goods(goods):
    print ",".join([good+"-"+str(amount) for good, amount in goods.items()])

def output_good(good, amount):
    print good+"-"+str(amount)

def current_turn_is(turn):
    print "T"
    return readline() == turn

turns = MARKET, PRODUCE, TRADING, SKIPPED = "M", "P", "T","S"
market_options = PURCHASE, SELL = "P", "S"
items = APRICOTS, BOARS, CANARIES, DAFFODILS, EARWIGS, NOTHING = "A", "B", "C", "D", "E", "X"

productivity = parse_goods(readline())
while True:
    product_to_produce = get_minimum(add_goods(current_goods(), productivity))
    print product_to_produce
    while current_turn_is(MARKET):
        print PURCHASE
        if readline() != SKIPPED:
            offered_good = parse_goods(readline())
            accepted_goods = parse_goods(readline())
            minimum = get_minimum(accepted_goods)
            current = current_goods()
            if minimum not in current or current[minimum] < accepted_goods[minimum]:
                print NOTHING
            elif accepted_goods[minimum] < offered_good.values()[0]:
                print minimum
            elif accepted_goods[minimum] == offered_good.values()[0] \
                    and productivity[minimum] > productivity[offered_good.keys()[0]]:
                print minimum
            else:
                print NOTHING

Answer 5

Ratio Trader

This bot offers products matching the ratio of his productivity

command.txt

python ratio.py

ratio.py

import sys

def current_goods():
    print "G"
    return parse_goods(readline())

def parse_goods(good_string):
    return dict([(a, int(b))
                 for a, b in [product.split("-")
                              for product in good_string.split(",")]])

def get_minimum(goods):
    cur_min = 200
    min_good = "X"
    for good, amount in goods.items():
        if amount < cur_min:
            min_good = good
            cur_min = amount
    return min_good

def get_maximum(goods):
    cur_max = -1
    max_good = "X"
    for good, amount in goods.items():
        if amount > cur_max:
            max_good = good
            cur_max = amount
    return max_good

def add_goods(x, y):
    return {k: int(x.get(k, 0)) + int(y.get(k, 0)) for k in set(x) | set(y)}

def readline():
    line = sys.stdin.readline().strip()
    if line == 'Q' or not line:
        exit()
    return line

def output_goods(goods):
    print ",".join([good+"-"+str(amount) for good, amount in goods.items()])

def output_good(good, amount):
    print good+"-"+str(amount)

def current_turn_is(turn):
    print "T"
    return readline() == turn

turns = MARKET, PRODUCE, TRADING, SKIPPED = "M", "P", "T", "S"
market_options = PURCHASE, SELL = "P", "S"
items = APRICOTS, BOARS, CANARIES, DAFFODILS, EARWIGS, NOTHING = "A", "B", "C", "D", "E", "X"

productivity = parse_goods(readline())
while True:
    current = current_goods()
    min_product = get_minimum(current)
    min_amount = current[min_product]
    product_to_produce = min_product if min_amount < 4 else get_minimum(productivity)
    print product_to_produce
    while current_turn_is(MARKET):
        print SELL
        if readline() != SKIPPED:
            current = current_goods()
            maximum = get_maximum(current)
            minimum = get_minimum(current)
            to_offer = {maximum: max(productivity[maximum]/productivity[minimum], 1)}
            output_good(minimum, 1)
            output_goods(goods=to_offer)

Answer 6

Family Farmers - Java

The five family farmers do their best to cover all production options with whoever can make the most in any category working on that category. However, after the initial assignments the family members all strike out on their own; they don't collude after the initial assignments. I may get around to having them help each other while trading.

FamilyFarmers.java

import java.io.IOException;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.FileLock;
import java.nio.file.FileSystems;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;
import java.util.Scanner;

public class FamilyFarmers {
    final int MIN_PRODUCTION_CUTOFF = 4; // If my decision making has ended up
                                            // with a family member producing
                                            // less than this number, he will
                                            // just produce his most productive
                                            // item
    final int NUMBER_PRODUCTS = 5;
    final int MAX_TRADES = 50; // The number of trades per phase
    final byte EOF = 04;
    final byte NEW_LINE = 10;
    final int BILLBOARD_SIZE = 1000;

    boolean alive = true;

    int[] myInventory;

    int myNumber;
    // Primarily, the line this instance of the program will be printing on in
    // the billboard number 0 will be the "boss", and will do a bunch of the
    // calculations (To avoid them being done multiple times)
    MappedByteBuffer familyBillboard;
    String myProduct; // What product (single string character) we will be
                        // making
    Scanner stdin = new Scanner(System.in);

    /**
     * @param args
     *            A string in the form A-#,B-#,C-#,D-#,E-# representing the
     *            productivity of each good.
     * @throws IOException
     * @throws InterruptedException
     * @throws UnexpectedPhaseTokenException
     */
    public static void main(String[] args) throws IOException, InterruptedException {
        new FamilyFarmers();
    }

    public FamilyFarmers() throws IOException, InterruptedException {
        Runtime.getRuntime().addShutdownHook(new Thread() {
            public void run() {
                familyBillboard.clear();
                familyBillboard.put(new byte[familyBillboard.limit()]);
                Runtime.getRuntime().halt(0);
            }
        });
        initialSetup();
        mainLoop();
    }

    protected void mainLoop() throws InterruptedException {
        int tradeCounter = 0; // 50 trades per phase
        String currentStage;
        int toTrade = -1;
        int toGet = -1;
        boolean purchase = false;

        while (alive) {
            System.out.println("T");
            currentStage = stdin.nextLine();
            if (currentStage.equals("P")) { // Production period
                System.out.println(myProduct);
                /*
                System.out.println("G");
                String currentInv = stdin.nextLine();
                myInventory = parseProducts(currentInv);
                toTrade = getMostProduct();
                toGet = getLeastProduct();
                */
                tradeCounter = 0;

            } else if (currentStage.equals("M")) { // Market
                System.out.println("G");
                String currentInv = stdin.nextLine();
                myInventory = parseProducts(currentInv);
                tradeCounter++;
                purchase = (Math.random() >= 0.5);
                toTrade = getMostProduct();
                toGet = getLeastProduct();

                // If my goods are fairly even, it's time to head home!
                if (myInventory[toTrade] - myInventory[toGet] <= 2) {
                    System.out.println("L");
                    continue;
                }

                // If I don't have much to trade...
                if (toTrade <= 6) {
                    // But my goods levels are fairly even...
                    if (toGet >= 4) {
                        // I'll just leave the market
                        System.out.println("L");
                    }
                }

                if (purchase) {
                    System.out.println("P");
                } else {
                    System.out.println("S");
                }

            } else if (currentStage.equals("T")) {
                String toSend = "";
                if (purchase) { // Buying
                    boolean finished = false;
                    String offer = stdin.nextLine();
                    offer += "," + stdin.nextLine();
                    String[] offers = parseOffer(offer);
                    int quantityOffered = Integer.parseInt(offers[0].split("-")[0]);
                    int productOffered = offers[0].split("-")[1].charAt(0) - 65;

                    // This loop will probably never get off the first
                    // iteration...
                    // Go through the offers, blindly pick the first one that
                    // looks good.
                    for (int index = 1; index < offers.length && !finished; index++) {
                        int quantityDesired = Integer.parseInt(offers[index].split("-")[0]);
                        int productDesired = offers[index].split("-")[1].charAt(0) - 65;

                        // If the request would leave me with less than two, I'm
                        // not interested
                        if (quantityDesired - (myInventory[productDesired]) > 2) {
                            // Too rich for my blood!
                            continue;
                        }
                        if (productDesired == toGet) {
                            // I'm not interested in trading what I'm trying to
                            // get!
                        }
                        if (productOffered == toGet) {
                            // Since this is what I want to trade for, I'll be
                            // willing to consider different offers than
                            // otherwise

                            if (quantityDesired <= quantityOffered * 1.25
                                    && myInventory[productDesired] - quantityDesired > 4) {
                                System.out.println((char) (productDesired + 65));
                                finished = true;
                            }

                            // If I would otherwise die without the product,
                            // I'll accept a really bad trade
                            // (Remember that the incoming offers are already
                            // sorted least to highest)
                            if (myInventory[toGet] < 2 && tradeCounter > MAX_TRADES / 2) {
                                System.out.println((char) (productDesired + 65));
                                finished = true;
                            }
                        }

                        // If the product is what I'm trying to trade, and the
                        // offer isn't too bad
                        if (productDesired == toTrade && quantityOffered * 1.25 <= quantityDesired) {
                            System.out.println((char) (productDesired + 65));
                            finished = true;
                        }

                        // If I am offered either as much as or more of
                        // something, I'll do it.
                        if (quantityOffered >= quantityDesired) {
                            System.out.println((char) (productDesired + 65));
                            finished = true;
                        }
                    }

                    if (!finished) {
                        // If we get this far, nothing struck my fancy
                        System.out.println("X");
                    }

                } else { // Selling
                    int[] toBuy = getSameProducts(toGet);

                    // Make some self-beneficial offers in the first few rounds.
                    if (tradeCounter <= 5) {
                        toSend = "" + ("2-" + ((char) (toTrade + 65)));
                        for (int index = 0; index < toBuy.length; index++) {
                            toSend += (",3-" + ((char) (toBuy[index] + 65)));
                        }
                    } else {
                        // Basic offer. Just offer 1:1 for what I want.
                        toSend = "" + ("2-" + ((char) (toTrade + 65)));
                        for (int index = 0; index < toBuy.length; index++) {
                            toSend += (",2-" + ((char) (toBuy[index] + 65)));
                        }
                    }

                    // If trading has been going for awhile and I would die the
                    // next turn, I frantically offer everything I have for what
                    // I need to survive one more turn. This is probably a
                    // terrible strategy!
                    if (myInventory[toGet] < 2 && tradeCounter > MAX_TRADES / 2) {
                        toSend += ("4-" + ((char) (toTrade + 65))) + ",2-" + ((char) (toGet + 65));
                    }

                    if (toSend.length() < 6) {
                        // I couldn't find enough to sell...
                        System.out.println(toSend + "," + toSend);
                        // That's safe, right?
                        break;
                    }

                    // Put the products I would accept on a line after the
                    // product I want to sell
                    String[] splitSend = toSend.split(",");
                    toSend = splitSend[0] + "\n";
                    boolean first = true; // Don't prepend a comma on the first string

                    for (int index = 1; index < splitSend.length; index++) {
                        if (!first){
                            toSend += ",";
                        }
                        toSend += splitSend[index];
                        first = false;
                    }

                    System.out.println(toSend);

                }

            } else if (currentStage.equals("S")) { // I was skipped! Darn it!
            } else {
                // AAK! I received a token I don't know what to do with! I must
                // be dead...
                alive = false;
            }
        }
    }

    /**
     * Returns the offers, sorted from least product desired to most, with the
     * product being offered at the first index
     * 
     * @param offer
     * @return String[] index 0 contains the product being offered, the
     *         following indicies are the desired products ordered from least to
     *         most
     */
    protected String[] parseOffer(String offer) {
        String[] splitOffers = offer.split(",");

        // Sort. Just using selection sort. The first index contains the string
        // with the product being asked for,
        // so should not be sorted.
        for (int index = 1; index < splitOffers.length; index++) {
            int indexOfMin = index;
            int minimum = Integer.parseInt(splitOffers[index].split("-")[0]);
            for (int jdex = index + 1; jdex < splitOffers.length; jdex++) {
                int thisValue = Integer.parseInt(splitOffers[jdex].split("-")[0]);
                if (thisValue < minimum) {
                    indexOfMin = jdex;
                    minimum = thisValue;
                }
            }
            String temp = splitOffers[index];
            splitOffers[index] = splitOffers[indexOfMin];
            splitOffers[indexOfMin] = temp;

        }

        return splitOffers;
    }

    /**
     * Returns an array of the indices of the product which I have the same
     * quantity of in myInventory
     * 
     * @param startingIndex
     *            - The index of a value to match
     * @return
     */
    protected int[] getSameProducts(int startingIndex) {
        int[] toReturn = new int[0];

        for (int index = startingIndex + 1; index < myInventory.length; index++) {
            if (myInventory[index] == myInventory[startingIndex]) {
                int[] temp = new int[toReturn.length + 1];
                for (int jdex = 0; jdex < toReturn.length; jdex++) {
                    temp[jdex] = toReturn[jdex];
                }
                temp[temp.length - 1] = index;
                toReturn = temp;
            }
        }

        return toReturn;
    }

    /**
     * Returns the index of the product which I have the least of in myInventory
     * I can't help but feel that this lacks object-oriented design...
     * 
     * @return
     */
    protected int getLeastProduct() {
        int toReturn = 0;

        for (int index = 1; index < myInventory.length; index++) {
            toReturn = myInventory[index] < myInventory[toReturn] ? index : toReturn;
        }

        return toReturn;
    }

    /**
     * Returns the index of the product which I have the most of in myInventory
     * I can't help but feel that this lacks object-oriented design...
     * 
     * @return
     */
    protected int getMostProduct() {
        int toReturn = 0;

        for (int index = 1; index < myInventory.length; index++) {
            toReturn = myInventory[index] > myInventory[toReturn] ? index : toReturn;
        }

        return toReturn;
    }

    /**
     * Returns an int[] containing the productivity of each product in
     * alphabetical order
     * 
     * @param products
     * @return
     */
    protected int[] parseProducts(String products) {
        int[] toReturn;
        // Split the string so that each line of the array has #-P
        String[] lineProductivities = products.split(",");

        // Split each string in the array so that it is just the number
        for (int index = 0; index < lineProductivities.length; index++) {
            lineProductivities[index] = lineProductivities[index].split("-")[0];
        }

        toReturn = new int[lineProductivities.length];

        for (int index = 0; index < lineProductivities.length; index++) {
            toReturn[index] = Integer.parseInt(lineProductivities[index]);
        }

        return toReturn;
    }

    /**
     * Append my productivity string to the family billboard. If the file was
     * empty when I got here (contained no newlines), I am the boss! The boss
     * gives orders.
     * 
     * @throws IOException
     * @throws InterruptedException
     */
    protected void initialSetup() throws IOException, InterruptedException {
        String input;
        myNumber = 0;
        FileChannel familyBillboardFC;
        Path billboardPath = FileSystems.getDefault().getPath("family_billboard.txt");
        FileLock billboardLock;
        byte[] argsByteArray;

        byte currentByte = 0;

        input = stdin.nextLine();

        // Open the file and lock it
        familyBillboardFC = FileChannel.open(billboardPath, StandardOpenOption.WRITE, StandardOpenOption.READ);
        billboardLock = familyBillboardFC.lock();

        // Map the contents of the file to a space in memory
        familyBillboard = familyBillboardFC.map(FileChannel.MapMode.READ_WRITE, 0, BILLBOARD_SIZE);

        // Convert the incoming string into an array of bytes
        argsByteArray = input.getBytes();

        for (int index = 0; index < BILLBOARD_SIZE; index++) {
            currentByte = familyBillboard.get();
            if (currentByte == NEW_LINE) {
                myNumber++;
                familyBillboard.mark();
            }
        }

        if (myNumber == 0) {
            familyBillboard.position(0);
            familyBillboard.mark();
        }
        familyBillboard.reset();

        for (byte b : argsByteArray) {
            familyBillboard.put(b);
        }
        familyBillboard.put(NEW_LINE);
        familyBillboard.put(EOF);

        billboardLock.release();

        Thread.sleep(100); // Give other programs a chance to launch

        // Boss needs to wait for awhile to make sure the others have finished
        // writing...
        // I don't have any idea how to do this in an intelligent fashion. It is
        // *probably* safe to sleep for a few hundred milliseconds, but I'm not
        // certain. Instead, I'll try to take out a new lock. If I succeed
        // twice, the file must be finished!
        int counter = 0;
        while (myNumber == 0) {
            billboardLock = familyBillboardFC.tryLock();
            if (billboardLock != null) {
                billboardLock.release();
                counter++;
            } else {
                counter = 0;
                Thread.sleep(10);
            }
            if (counter >= 2) {
                giveOrders();
                break;
            }
        }

        byte foo = familyBillboard.get();
        // Until the boss has written out the instructions, sleep
        while (foo < 65) {
            Thread.sleep(10);
            familyBillboard.reset();
            foo = familyBillboard.get();
        }

        familyBillboard.reset();
        myProduct = String.valueOf((char) familyBillboard.get());
    } // initialSetup()

    /**
     * Run by the boss. Tries to sort the family so that every product is
     * covered and so that whoever can produce the most of a product is
     * producing it. Writes the character code representing the product to
     * produce to the first character of the relevant line in the family
     * billboard.
     */
    protected void giveOrders() {
        final int MAX_LINE_LENGTH = 24;
        int numberMembers = 0;
        byte currentByte = 0;
        Integer[][] productivities; // Table of member's productivities
        char[] selections; // Who will make what. selections[#] = the production
                            // letter for member #

        familyBillboard.position(0);

        // I have seen the rules to these games change. It's easy for me to
        // accommodate more (or less than) 5 instances now. It may not be easy
        // later
        while (currentByte != EOF) {
            currentByte = familyBillboard.get();
            if (currentByte == NEW_LINE) {
                numberMembers++;
            }
        }
        currentByte = 0;
        familyBillboard.reset();

        selections = new char[numberMembers];

        productivities = new Integer[numberMembers][NUMBER_PRODUCTS];

        for (int index = 0; index < numberMembers; index++) {
            byte[] currentLineBytes = new byte[MAX_LINE_LENGTH];
            String currentLine;

            // Read the next line
            for (int jdex = 0; jdex < currentLineBytes.length; jdex++) {
                currentByte = familyBillboard.get();
                if (currentByte == NEW_LINE) {
                    break;
                }
                currentLineBytes[jdex] = currentByte;
            }
            currentLine = new String(currentLineBytes);
            currentByte = 0;

            int[] lineProductivities = parseProducts(currentLine);

            // Need to iterate to get the int[] to Integer[]
            for (int jdex = 0; jdex < NUMBER_PRODUCTS; jdex++) {
                productivities[index][jdex] = lineProductivities[jdex];
            }

        }

        // If there are at least as many producers as products, select the most
        // productive for each producer. If there are overlaps, move the smaller
        // one to the second most productive and re-check for overlaps. If there
        // are overlaps and the productivity is tied, compare the second highest
        // and so on.
        // TODO What if members > 5?
        if (numberMembers <= NUMBER_PRODUCTS) {
            int[] overlapResult;
            for (int index = 0; index < selections.length; index++) {
                selections[index] = (char) (maxInArray(productivities[index]) + 65);
                // Can convert from a max value in productivities to a
                // human-readable character by adding 65, since 0 -> A, 1 -> B,
                // etc.
            }

            int counter = 0; // I imagine there is a possibility of this loop
                                // not terminating. I will use this counter to
                                // forcefully break it.

            // While there is an overlap
            while ((overlapResult = arrayHasOverlaps(selections)) != null && overlapResult[0] != -1) {
                byte productIndex = (byte) (selections[overlapResult[0]] - 65);
                // 0 through the number of production options, where A = 0, B =
                // 1, etc.
                if (productivities[overlapResult[0]][productIndex] > productivities[overlapResult[1]][productIndex]) {
                    int index = findNextHighestFromIndex(productivities[overlapResult[1]], productIndex);
                    selections[overlapResult[1]] = (char) (index + 65);
                }
                if (productivities[overlapResult[1]][productIndex] > productivities[overlapResult[0]][productIndex]) {
                    int index = findNextHighestFromIndex(productivities[overlapResult[0]], productIndex);
                    selections[overlapResult[0]] = (char) (index + 65);
                }
                // Things are beginning to get mega hairy
                if (productivities[overlapResult[0]][productIndex] == productivities[overlapResult[1]][productIndex]) {
                    int index0 = findNextHighestFromIndex(productivities[overlapResult[0]], productIndex);
                    int index1 = findNextHighestFromIndex(productivities[overlapResult[1]], productIndex);
                    if (productivities[overlapResult[0]][index0] > productivities[overlapResult[1]][index1]) {
                        selections[overlapResult[0]] = (char) (index0 + 65);
                    } else {
                        // I can't be bothered to go any further with this... If
                        // they're tied here, then to heck with it!
                        selections[overlapResult[1]] = (char) (index1 + 65);
                    }
                }

                counter++;
                if (counter > BILLBOARD_SIZE) {
                    break;
                }
            }
        }

        // Check for less than my minimum cutoff. If one is, set it to its max.
        for (int index = 0; index < selections.length; index++) {
            byte b = (byte) (selections[index] - 65);
            if (productivities[index][b] < MIN_PRODUCTION_CUTOFF) {
                selections[index] = (char) (maxInArray(productivities[index]) + 65);
            }
        }

        // Write the product to produce to the correct line
        familyBillboard.position(0);
        familyBillboard.put((byte) selections[0]);
        // If we find a newline, write the selected character to the next
        // spot. Otherwise, read the next character
        for (int index = 1; index < selections.length;) {
            byte thisByte = familyBillboard.get();
            if (thisByte == NEW_LINE) {
                familyBillboard.put((byte) selections[index]);
                index++;
            }
        }
    }

    /**
     * Look through the array. Find an element that is either later in the array
     * and <= the value at the incoming index and > the value at the toReturn
     * index, or earlier in the array and < the value at the current index and >
     * the value at toReturn. If we weren't able to set the new index (Maybe we
     * are already at the max value) return the index of the largest value
     * 
     * @param array
     *            the array to search in
     * @param incomingIndex
     *            the index of the value to begin searching with
     * @return an index as described
     */
    protected int findNextHighestFromIndex(Integer[] array, int incomingIndex) {
        int toReturn = incomingIndex;
        int comparisonValue = -1; // The value at toReturn
        int index = (incomingIndex + 1) % array.length;

        for (int counter = 0; counter < array.length; counter++) {
            if (index > incomingIndex && array[index] == array[incomingIndex]) {
                // If we have found an equal value later in the array, return
                // immediately. In the unlikely event everything is equal,
                // don't just take the value at the bottom index!
                return index;
            }
            if (index > incomingIndex && array[index] < array[incomingIndex] && array[index] > comparisonValue) {
                toReturn = index;
                comparisonValue = array[toReturn];
            }
            if (index < incomingIndex && array[index] < array[incomingIndex] && array[index] > comparisonValue) {
                toReturn = index;
                comparisonValue = array[toReturn];
            }

            index++;
            index %= array.length; // How often do you get to use %= ?
        }

        if (comparisonValue == -1) {
            // In the unlikely event we weren't able to set comparisonValue
            // (maybe we are already at the minimum?)
            toReturn = maxInArray(array);
            // This will probably contribute to those endless loops I mentioned
            // above!
        }

        return toReturn;
    }

    /**
     * Checks the array for any two elements being the same. If two are, return
     * the indices. If not, return {-1, -1}
     * 
     * @param selections
     *            The array to examine
     * @return Indices of the overlapping elements or {-1, -1}
     */
    protected int[] arrayHasOverlaps(char[] selections) {
        int[] toReturn = new int[] { -1, -1 };
        for (int index = 0; index < selections.length - 1; index++) {
            for (int jdex = index + 1; jdex < selections.length; jdex++) {
                if (selections[index] == selections[jdex]) {
                    toReturn[0] = index;
                    toReturn[1] = jdex;
                    return toReturn;
                }
            }
        }
        return toReturn;
    }

    /**
     * Returns the index of the max value of an array. In the case of a tie,
     * returns the earliest index.
     * 
     * @param array
     *            the array to read
     * @return the index of the largest element in the array
     */
    protected <T extends Comparable<T>> byte maxInArray(T[] array) {
        byte currentMax = 0;
        for (byte index = 0; index < array.length; index++) {
            currentMax = array[index].compareTo(array[currentMax]) > 0 ? index : currentMax;
        }
        return currentMax;
    }
}

command.txt

cd bots/family_farmer && java FamilyFarmers

It can be compiled with

javac FamilyFarmer.java

There should also be another blank file, family_billboard.txt, in the bots/family_farmer folder.

Answer 7

Introvert - Java

This bot is so introverted, it would rather die than talk to anyone in trading, so it immediately leaves market if it is there. However, it doesn't want to die so it tries to keep its supplies up as long as possible.

Introvert.java

import java.util.Scanner;

public class Introvert{

    static int[] current = {10,10,10,10,10};
    static int[] potentialProduction = new int[5];
    static boolean alive = true;

    public static void main(String[] args){
        Scanner s = new Scanner(System.in);
        String input = s.nextLine();
        String[] inputArray = input.split(",");
        for(int i = 0; i < 5; i++){
            potentialProduction[i] = Integer.parseInt(inputArray[i].replaceAll("\\D+",""));
        }

        while(alive){
            int pos = decideProduction();
            produce(pos);
            System.out.println("L");
            for(int i = 0; i < 5; i++){
                current[i] -= 2;
                if(current[i] < 0)
                    alive = false;
            }
        }
        s.nextLine(); //read final `q` message
    }

    public static int decideProduction(){
        int lowestPotential = 9999;
        int lowestPotentialPosition = 9999;
        for(int i = 0; i < 5; i++){
            if(current[i] == 2 || current[i] == 3){
                lowestPotentialPosition = i;
                break;
            }
            int potential = current[i] + potentialProduction[i];
            if(potential < lowestPotential){
                lowestPotential = potential;
                lowestPotentialPosition = i;
            }
        }
        switch(lowestPotentialPosition){
            case 0: System.out.println("A"); return 0;
            case 1: System.out.println("B"); return 1;
            case 2: System.out.println("C"); return 2;
            case 3: System.out.println("D"); return 3;
            case 4: System.out.println("E"); return 4;
            default: System.out.println("A"); return 0;
        }
    }

    public static void produce(int pos){
        current[pos] += potentialProduction[pos];
    }

}

command.txt

java Introvert

Compile with

javac Introvert.java

Note: I did this on my lunch break and my work computer doesn't have the jdk or python so I have not been able to test it at all. If it does not work let me know and I will try to fix it.

Answer 8

Random Ando

Every KOTH should have a random bot. Coded, hopefully, so that it won't make invalid deals (like trying to sell more than what it has in stock).

--RandomAndo

math.randomseed(os.time()) math.random()math.random()math.random()

ITEMS = {"A", "B", "C","D", "E"}
MARKETOPTION = {"P", "S"}
MyGoods = {0,0,0,0,0}

local function readline() -- checks for the dying "Q" or just reads line
    local line = io.read("*l")
    if line == "Q" then
        os.exit()
    end

    return line
end

local function getCurrentTurn() -- asks for M,T,P
    print("T")
    return readline()
end

local function getRandom(array) -- returns for a random element in array
    local r=math.random(#array)
    return array[r]
end

local function getRandomMyItems() -- make a list of items I have and return a random one (no more than one of)
    local rgood=math.random(5)
    local amount=1
    while MyGoods[rgood] <= 0 do
        rgood=math.random(5)
    end
    return amount.."-"..ITEMS[rgood]
end

local function parseGoods(goodString) -- specialized to getMyGoods atm
    local goods={0,0,0,0,0}
    local c = 1
    example = "5-A,6-B,3-C,12-D,4-E"
    for good in goodString:gmatch("%d+%p[ABCDE]") do
        goods[c]=goods[c]+good:match("%d+")
        c=c+1
    end

    return goods
end

local function getMyGoods() -- asks for my goods
    print("G")
    local temp = parseGoods(readline())
    for i=1,5 do
        MyGoods[i]=temp[i]
    end
end


productivity = readline() -- doesn't matter

while true==true do

    print(getRandom(ITEMS)) -- produce random item

    while getCurrentTurn()=="M" do
        getMyGoods()

        local action=getRandom(MARKETOPTION) -- make a random market decision
        if action == "S" then -- offer to sell 1 of a random item I  have in stock, will take any 2 offered
            print("S")
            if readline()=="T" then
                print(getRandomMyItems())
                print("2-A,2-B,2-C,2-D,2-E")
            end
        elseif action == "P" then -- if I can do the deal, I will
            print("P")
            if readline()=="T" then
                local offered=readline()
                local accepted =readline()
                local taccepted={}
                for i in accepted:gmatch("%d+%p[ABCDE]") do
                    oitem =i:match("[ABCDE]")
                    oamount = i:match("%d+")
                    for k=1,5 do
                        if ITEMS[k]==oitem and MyGoods[k]>=tonumber(oamount) then
                            table.insert(taccepted, oitem)
                        end
                    end
                    if #taccepted>=1 then
                        print(getRandom(taccepted))
                    else
                        print("X")
                    end
                end
            end
        elseif action == "L" then
            print("L")
        end
    end
end

command.txt should be:

lua RandomAndo.lua