Yarr! A map to the hidden treasure!

Question

Introduction

"Yarr!! We had a laddie who called himself a "programmer" make a map t' our hidden treasure! But 'tis written wit' weird numbers 'n letters! "E5, N2, E3"... what does it even mean? Madness! Can't even scribe a proper treasure map, t' useless cretin. Fix it fer us! We'll gift ye a share o' t' treasure!"

Challenge Description

A group of pirates are having trouble reading a treasure map. Can you write a program to convert it into a more... piratey form?

As input, you'll receive the original treasure map. It's a list of comma separated strings, each string which consists of a letter portion (which tells the pirates which direction they need to walk in), and a number portion (which tells the pirates how many steps to take in that direction). For instance, the following treasure map:

E2,N4,E5,S2,W1,S3

would mean, "walk two steps to the east, walk four steps to the north, walk five steps to the east, walk two steps to the south, walk one step to the west, then walk three steps to the south."

As output, you'll output the map in a graphical form, using the characters >, ^, v, and < as pointers. Here's the output for the above input:

  >>>>>v
  ^    v
  ^   v<
  ^   v
>>^   X

Notice that we've replaced the last step to the south with an X instead. This is because the last step is where the treasure is, and as we all know, pirates must have an X on their treasure maps, otherwise they won't know how to read it.

By the way, the map won't ever cross itself, so you don't need to worry about dealing with overlaps. Also, you are allowed to have a trailing new line at the end of the output.

Sample Inputs and Outputs

S5,W2

 v
 v
 v
 v
 v
X<

N1,E1,S1,E1,N1,E1,S2

>v>v
^>^X

N1

X

N6,E6,S6,W5,N5,E4,S4,W3,N3,E2,S2,W1,N2

>>>>>>v
^>>>>vv
^^>>vvv
^^^Xvvv
^^^^<vv
^^^<<<v
^^<<<<<

E21,S2

>>>>>>>>>>>>>>>>>>>>>v
                     X

N12,E11,S12,W2,N4

>>>>>>>>>>>v
^          v
^          v
^          v
^          v
^          v
^          v
^          v
^          v
^        X v
^        ^ v
^        ^ v
^        ^<<

Answer 1

Ruby, 213 209 198 186 178

M={};x=0,m=q=0
gets.scan(/.(\d+)/){?1.upto($1){m,y=x
x[d=$&.ord%10%7-2]+=1|($u=M[y]||={})[m]=d
m<q&&q=m}}
$u[m]=2
puts M.sort.map{|_,b|(q..b.max[0]).map{|k|">vX <^"[b[k]||3]}*""}

Pass input via stdin.

This uses a y -> x -> char dictionary to construct the map, where both x and y can be negative. Once the input has been parsed, the global minimum of the x coordinate is extracted. For each row, it then iterates over a range going from the global minimum to the maximum index for the current line, and prints the correct character for that index.

To stay with the theme, the expressions to turn NESW into the proper indices were shamelessly pirated from Sp3000's answer.

Original version that used a [x,y] -> char dictionary:

M={};x=0,0
gets.scan(/.(\d+)/){(?1..$1).map{x[d=$&.ord%10%7-2]+=1|M[$y=x+[]]=d}}
M[$y]=2
a,*q=M.minmax.flatten
M.map{|(x,y),v|($*[y-M.map{|a,|a[1]}.min]||=?\s.*q[2]-a)[x-a]=">vX<^"[v]}
puts$*.map &:rstrip

Answer 2

Python 2, 249 248 244 239 237 bytes

D={}
m=X=Y=0
for s in input().split(","):d=ord(s[0])%10%7;exec"a,b=X,Y;E=D[Y]=D.get(Y,{});E[X]='<^>v'[d];m=min(m,X);%c+=d-2|1;"%(88+d%2)*int(s[1:])
D[b][a]="X"
for Y in sorted(D):print"".join(D[Y].get(n," ")for n in range(m,max(D[Y])+1))

Input like "E2,N4,E5,S2,W1,S3".

NSEW is mapped to [1, 3, 2, 0] by d=ord(c)%10%7. Whether to change y or x is then decided by d%2, and whether to increment or decrement is decided by d-2|1. The first and third expressions were found by brute force.

Other than that, it's a simple usage of a nested dictionary of the form {y: {x: char}}.

(Thanks to @joriki for help with mapping)

Answer 3

Javascript (ES6), 260

This was an interesting one...

Thanks @ETHproductions, @edc65, and @vihan for the help!

s=>{z=o=""
m=[]
q=x=y=2e3
s.split`,`.map(v=>z+=v[0].repeat(+v.slice(1)))
for(i=0;d=z[i];q=x<q?x:q)(m[y]=m[y]||[])[x]=z[++i]?d=="N"&&--y?"^":d=="S"&&++y?"v":d=="W"&&--x?"<":++x?">":o:"X"
m.map(a=>a.map((b,j)=>o+=" ".repeat(-p-1+(p=j))+b,p=q-1,o+=`
`))
return o}

This defines an anonymous function, so to call it add f= to the beginning to give it a name.

To test: console.log(f("E2,N4,E5,S2,W1,S3"))

Explanation:

s=>{ //define function w/ parameter s
z=o=""      //z=modified input, o=final output
m=[]        //map of characters
q=x=y=2e3   //q=minimum value of x; x+y=coordinates. These start high to leave room to go backwards
s.split`,`.map(v=>z+=v[0].repeat(+v.slice(1)))    //change "N3,E4" -> "NNNEEEE", and put in z
for(i=0;d=z[i];q=x<q?x:q)   //for each direction d in z, while updating q:
    (m[y]=m[y]||[])[x]=     //in the right place on the map, put:
        z[++i]?                 //if last character of z, "X"
            d=="N"&&--y?"^":    
            d=="S"&&++y?"v":    //otherwise get the right character and change x+y accordingly
            d=="W"&&--x?"<":
            ++x?">":o
        :"X"
m.map(a=>a.map((b,j)=>o+=" ".repeat(-p-1+(p=j))+b,p=q-1,o+=`
`)) //dump map to o, with correct padding
return o}   //return

Answer 4

PHP, 431 417 bytes

$g=explode(',',$argv[1]);$x=$y=$a=$b=$c=$d=$e=$f=0;
foreach($g as$i=>$h){list($k,$l,$m)=
    ['N'=>[-1,0,'^'],'E'=>[0,1,'>'],'S'=>[1,0,'v'],'W'=>[0,-1,'<']][$h[0]];
    for($s=substr($h,1);$s--;){$z[$f=$y][$e=$x]=$m;$y+=$k;$x+=$l;}
    if($i==count($g)-1){$x=$e;$y=$f;}
    $a=min($a,$x);$b=max($b,$x);$c=min($c,$y);$d=max($d,$y);
}$z[$y][$x]='X';for($y=$c;$y<=$d;$y++)
{$o='';for($x=$a;$x<=$b;$x++)$o.=$z[$y][$x]?:' ';echo rtrim($o)."\n";}

Put it into a file (treasure.php), remove the indentation, join the lines (it is wrapped here for readability), put the <?php marker at the beginning of the file (not displayed here as it is technically not a part of the program).

Example of execution:

$ php -d error_reporting=0 treasure.php E2,N4,E5,S2,W1,S3
  >>>>>v
  ^    v
  ^   v<
  ^   v
>>^   X
$

The option -d error_reporting=0 is needed to suppress notices about values not found at specified indices in $z.

Update:

While I was preparing the ungolfed version of the code for posting I discovered it contained two unneeded assignments (12 bytes) and a whitespace that can be removed(as$i); also, by replacing a while with a for loop and squeezing an assignment into it (not possible using the while loop) I saved another byte.

Answer 5

Perl, 702 613 546 474 439 338 260 bytes

Thanks to Dom Hastings for his help and his supergolfed version.
The code uses a 2D array.

Version by Dom Hastings:

$x=$y=$a=$b=99;map{/^./;$a=($c=$x)<$a?$x:$a,$A=$x>$A?$x:$A,$b=($C=$y)<$b?$y:$b,$B=$y>$B?$y:$B,$q[$c][$C]={split'','W<E>N^Sv'}->{$&},$x+={W,-1,E,1}->{$&},$y+={N,-1,S,1}->{$&}for 1..$'}split',',pop;$q[$c][$C]=X;for$y($b..$B){print$q[$_][$y]||$"for$a..$A;print$/}

My lesser golfed version of 338 bytes (for reference):

@m=split(',',pop);$x=$y=$a=$b=99;map{($d,$s)=/^(.)(.+)$/;for(1..$s){$c=$x;$C=$y;if($x<$a){$a=$x}if($x>$A){$A=$x}if($y<$b){$b=$y}if($y>$B){$B=$y}if($d eq"W"){$r="<";$x--}if($d eq"E"){$r=">";$x++}if($d eq"N"){$r="^";$y--}if($d eq"S"){$r=v;$y++}$q[$c][$C]=$r}}@m;$q[$c][$C]=X;for$y($b..$B){for$x($a..$A){$t=$q[$x][$y];print$t?$t:$"}print$/}

Test

$ perl piratemap_golf.pl E4,N3,W6,S10,W1,S1,E5,N1,W2,N6,E6,N5,W10,S1,E2
v<<<<<<<<<<
>Xv<<<<<< ^
  v     ^ ^
  v     ^ ^
  v >>>>^ ^
  v >>>>>>^
  v ^
  v ^
  v ^
  v ^
  v ^
 v< ^<<
 >>>>>^

Answer 6

Python 2, 394 bytes

Run the program then paste into standard input as e.g. "E2,N4,E5,S2,W1,S3"

m=input().split(',')
def f(x,y,h,o,s=[]):
 for c in m:
  for _ in range(int(c[1:])):
   a,b,l={'E':(1,0,'>'),'W':(-1,0,'<'),'N':(0,1,'^'),'S':(0,-1,'v')}[c[0]]
   if o:o[h-y][x]=l
   s+=[(x,y)];x+=a;y+=b
 if o:o[h-y+b][x-a]='X'
 return s
p,q=zip(*f(*[0]*4))
w,h=max(p)-min(p),max(q)-min(q)
o=[[' ']*-~w for _ in range(h+1)]
f(-min(p),-min(q),h,o)
print'\n'.join(["".join(l).rstrip()for l in o])

This is not very optimized. First it runs through the input to record the path. Then it does some math to determine the right starting position and size of o. Then it runs through again and sets the appropriate entries of o as one of >v<^X. The main cleverness is in reusing the same function for both these traversals.

Answer 7

PHP, 496 514 528

I tried my luck in PHP, the result is rather long, I still want to post it, just for fun.

function a($c){global$a,$b;$a[$b[1]][$b[0]]=$c;}$c=explode(',',$argv[1]);$a=[];$b=[0,0];foreach($c as$d=>$e){$f=substr($e,1);if($d==count($c)-1)$f--;for($i=0;$i++<$f;){if($e[0]==N){a('^');$b[1]--;}elseif($e[0]==E){a('>');$b[0]++;}elseif($e[0]==S){a(v);$b[1]++;}else{a('<');$b[0]--;}}}a(X);$d=$e=$f=$g=0;foreach($a as$y=>$h){$f=min($f,$y);$g=max($g,$y);foreach($h as$x=>$i){$d=min($d,$x);$e=max($e,$x);}}for($y=$f;$y<=$g;$y++){for($x=$d;$x<=$e;$x++)echo isset($a[$y][$x])?$a[$y][$x]:' ';echo "
";}

Ungolfed

<?php

    function setInMap($char) {
        global $map, $position;
        $map[$position[1]][$position[0]] = $char;
    }

    $instructions = explode(',', $argv[1]);

    $map = [];

    $position = [0, 0];

    foreach($instructions as $index => $instruction) {
        $count = substr($instruction, 1);
        if($index === count($instructions) - 1) {
            $count--;
        }
        for($i = 0; $i < $count; $i++) {
            if($instruction[0] === 'N') {
                setInMap('^');
                $position[1]--;
            } elseif($instruction[0] === 'E') {
                setInMap('>');
                $position[0]++;
            } elseif($instruction[0] === 'S') {
                setInMap('v');
                $position[1]++;
            } else($instruction[0] === 'W') {
                setInMap('<');
                $position[0]--;
            }
        }
    }
    setInMap('X');

    $minX = $maxX = $minY = $maxY = 0;
    foreach($map as $y => $row) {
        $minY = min($minY, $y);
        $maxY = max($maxY, $y);
        foreach($row as $x => $cell) {
            $minX = min($minX, $x);
            $maxX = max($maxX, $x);
        }
    }
    for($y = $minY; $y <= $maxY; $y++) {
        for($x = $minX; $x <= $maxX; $x++) {
            if(isset($map[$y][$x])) {
                echo $map[$y][$x];
            } else {
                echo ' ';
            }
        }
        echo "\n";
    }

?>

Answer 8

XQuery 3.0, 498

declare variable $v external;let $m:=<v>{tokenize($v,',')!(for $j in(1 to xs:int(substring(.,2)))return<c>{translate(substring(.,1,1),'NESW','^>v<')}</c>)}</v>/c!(let $p:=./preceding-sibling::c return<p x="{count($p[.='>'])-count($p[.='<'])}" y="{count($p[.='v'])-count($p[.='^'])}">{if(./following::*)then .else'X'}</p>)for $y in(min(xs:int($m/@y))to max(xs:int($m/@y)))return string-join(for $x in(min(xs:int($m/@x))to max(xs:int($m/@x)))let $d:=$m[@x=$x and @y=$y]return if($d)then$d else' ','')

XQuery isn't often even slightly competitive, so this was fun.

Ungolfed

declare variable $v external;
let $map := <vector>{ tokenize($v,',') ! 
        (for $j in (1 to xs:int(substring(.,2)))
            return <step>{ translate(substring(.,1,1),'NESW','^>v<') }</step> ) 
         }</vector>/step !
            (let $path_so_far := ./preceding-sibling::step
            return <point 
                x="{ count($path_so_far[.='>']) - count($path_so_far[.='<']) }" 
                y="{ count($path_so_far[.='v']) - count($path_so_far[.='^']) }">
                {if(./following::*) then string(.) else 'X'}
            </point>)
for $y in (min(xs:int($map/@y)) to max(xs:int($map/@y)))
return string-join(
    for $x in (min(xs:int($map/@x)) to max(xs:int($map/@x)))
    let $d := $map[@x=$x and @y=$y]
    return if($d) then string($d) else ' '
    ,'')

Answer 9

JavaScript (ES6), 244 249 274

Leading spaces and newlines added for clarity and not counted, except the newline near the end in the join call, that is significant and counted.

Test running the snippet (being ECMAScript 6, Firefox and Safari 9 only)

F=m=>(
  x=y=0,p=[],
  m.replace(/\w(\d+)/g,(d,z)=>{
    for(d='NWSE'.search(d[0]);
        z--&&(p=~x?~y?p:[y=0,...p]:p.map(r=>' '+r,x=0));
        p[u=y]=(w=r.slice(0,x))+'^<v>'[d]+(v=r.slice(x+1)),
        d&1?x+=d-2:y+=d-1)
      for(r=p[y]||'';!r[x];)r+=' ';
  }),
  p[u]=w+'X'+v,
  p.join`
`
)

// TEST

out=x=>O.innerHTML+=x.replace(/</g,'&lt;')+'\n'

;['S5,W2','N1,E1,S1,E1,N1,E1,S2','N1','N6,E6,S6,W5,N5,E4,S4,W3,N3,E2,S2,W1,N2','E21,S2','N12,E11,S12,W2,N4']
.forEach(a=>out(a+'\n'+F(a)+'\n'))

<pre id=O></pre>

Answer 10

C, 557

main(_,a,minX,maxX,minY,maxY,x,y,v,dir,dist)char**a;char*v;{char o[998][999];for(y=0;y-998;++y){for(x=0;x-998;++x)o[y][x]=32;o[y][998]=0;}y=x=minY=minX=maxY=maxX=499;v=a[1];while(*v){dir=*v++;dist=atoi(v);while(*v&&*v!=44)v++;v+=!!*v;if(dir==78){while(dist--)o[y--][x]=94;if(y<minY)minY=y;y+=!*v;}if(dir==69){while(dist--)o[y][x++]=62;if(x>maxX)maxX=x;x-=!*v;}if(dir==83){while(dist--)o[y++][x]=86;if(y>maxY)maxY=y;y-=!*v;}if(dir==87){while(dist--)o[y][x--]=60;if(x<minX)minX=x;x+=!*v;}}o[y][x]=88;for(y=minY;y<=maxY;++y){o[y][maxX+1]=0;puts(o[y]+minX);}}

Ungolfed version:

#include <stdio.h>

#define MAX_WIDTH 998
#define MAX_HEIGHT 998

int main(int argc, char *argv[]) {
    int minX,maxX,minY,maxY;
    int x,y;
    char output[MAX_HEIGHT][MAX_WIDTH+1];
    char *v;

    for (y=0; y<MAX_HEIGHT; ++y) {
        for (x=0; x<MAX_WIDTH; ++x) 
            output[y][x] = ' ';
        output[y][MAX_WIDTH] = 0;
    }

    x = minX = maxX = MAX_WIDTH/2;
    y = minY = maxY = MAX_HEIGHT/2;

    v = argv[1];
    while (*v) {
        char dir; int dist;
        dir = *(v++);
        dist = atoi(v);
        while (*v && *v != ',') v++;
        if (*v) v++;

        switch (dir) {
            case 'N':case 'n':
                while (dist--) output[y--][x] = '^';
                if (y < minY) minY = y;
                if (!*v) y++;
                break;
            case 'E':case 'e':
                while (dist--) output[y][x++] = '>';
                if (x > maxX) maxX = x;
                if (!*v) x--;
                break;
            case 'S':case 's':
                while (dist--) output[y++][x] = 'v';
                if (y > maxY) maxY = y;
                if (!*v) y--;
                break;
            case 'W':case 'w':
                while (dist--) output[y][x--] = '<';
                if (x < minX) minX = x;
                if (!*v) x++;
                break;
        }
    }

    output[y][x] = 'x';
    for (y = minY; y <= maxY; ++y) {
        output[y][maxX+1] = 0;
        puts(output[y]+minX);
    }

    return 0;
}

Dynamic memory allocation isn't much harder, but malloc is far too long an identifier to be used in code golf. I feel like there should be some kind of PCG.h header legally auto-included for golfing in c, just to shorted some identifiers.

Answer 11

Groovy, 359

c=args[0].split(',').collect{[it[0],it[1..-1]as int]}
m=[[]]
x=y=0
d=["N":["^",0,1],"S":["v",0,-1],"E":[">",1,0],"W":["<",-1,0]]
c.each{z->(1..z[1]).each{if(x<0){m*.add(0," ");x=0};if(y<0){m.add(0,[]);y=0};m[y]=m[y]?:[];m[y][x]=d[z[0]][0];if(c.last()==z&&it==z[1])m[y][x]='X';y+=d[z[0]][2];x+=d[z[0]][1]}}
m.reverse().each{println it.collect{it?:" "}.join()}

Answer 12

Common Lisp - 603

(lambda(s)(do((x 0)i(y 0)j(p 0)r(q 0)(g(mapcar(lambda(x)`(,(aref x 0),(parse-integer x :start 1)))(split-sequence:split-sequence #\, s))(cdr g))c)((not g)(setf x 0 y 0)(dolist(e(stable-sort(sort r #'<= :key #'car)#'< :key #'cadr))(dotimes(_(-(cadr e)p y))(terpri)(incf y)(setf x 0))(dotimes(_(-(car e)q x))(princ" ")(incf x))(princ(caddr e))(incf x)))(case(caar g)(#\N(setf i 0 j -1 c #\^))(#\E(setf i 1 j 0 c #\>))(#\W(setf i -1 j 0 c #\<))(#\S(setf i 0 j 1 c #\v)))(dotimes(_(-(cadar g)(if(cdr g)0 1)))(push`(,x,y,c)r)(incf x i)(incf y j))(setf q(min q x)p(min p y))(unless(cdr g)(push`(,x,y #\X)r))))

Array-free implementation: prints from top to bottom, from left to right.

• Parse and expands directions into a trace of (x y char) elements:

  The simple "N3" input produces ((0 0 #\^) (0 -1 #\^) (0 -2 #\X))

• Also, compute the minimal x and y
• Sort the resulting trace by y first and then by x

• Iterate over the sorted list while moving cursor

  1. Add newlines and spaces to move current cursor at right position
  2. When at position x - minx, y - miny, print the desired character

Examples

(loop for input in  '("N6,E6,S6,W5,N5,E4,S4,W3,N3,E2,S2,W1,N2" 
                      "N1,E1,S1,E1,N1,E1,S2" 
                      "N12,E11,S12,W2,N4")
      do (fresh-line)
         (terpri)
      (funcall *fun* input))

Result:

>>>>>>v
^>>>>vv
^^>>vvv
^^^Xvvv
^^^^<vv
^^^<<<v
^^<<<<<

>v>v
^>^X

>>>>>>>>>>>v
^          v
^          v
^          v
^          v
^          v
^          v
^          v
^          v
^        X v
^        ^ v
^        ^ v
^        ^<<

Answer 13

CoffeeScript, 303  285 bytes

Y=(s)->o=[];t=l=x=y=0;q='';q+=s[0]for[1..s[1..]]for s in s.split ',';q=q[..-2];(i='NWSE'.search c;(o[y]?=[])[x]='^<v>'[i];j=(i&2)-1;x+=j*(i&1);y+=j*(!(i&1));y<t&&t=y;x<l&&l=x)for c in q;(o[y]?=[])[x]='X';((o[y][x]||' 'for x in[l...o[y].length]).join ''for y in[t...o.length]).join '\n'

<script src="http://coffeescript.org/extras/coffee-script.js"></script>
<script type="text/coffeescript">
Y=(s)->o=[];t=l=x=y=0;q='';q+=s[0]for[1..s[1..]]for s in s.split ',';q=q[..-2];(i='NWSE'.search c;(o[y]?=[])[x]='^<v>'[i];j=(i&2)-1;x+=j*(i&1);y+=j*(!(i&1));y<t&&t=y;x<l&&l=x)for c in q;(o[y]?=[])[x]='X';((o[y][x]||' 'for x in[l...o[y].length]).join ''for y in[t...o.length]).join '\n'

#------------------
document.write '<pre>'
z=[
  'E2,N4,E5,S2,W1,S3'
  'S5,W2'
  'N1,E1,S1,E1,N1,E1,S2'
  'N1'
  'N6,E6,S6,W5,N5,E4,S4,W3,N3,E2,S2,W1,N2'
  'E21,S2'
  'N12,E11,S12,W2,N4'
]
for w in z
  document.write "\n\n#{w}\n"
  document.write Y(w).replace /</g,'&lt;'
  
</script>

Answer 14

Jelly, 61 60 bytes

“ESWN”iⱮo)µịØ.,U;N$¤Wẋɗ/€Ẏḣ1;Ɗ+\ṖZṂ€ạƊ‘ŒṬ€a"Œṙ-0¦$Sị“>v<^X ”

Try it online!

A monadic link taking as its argument the directions as a list of lists, each of which has the compass direction character as its first member and the number of moves as an integer as its second. Returns a list of Jelly strings representing the map.