Implement t9-like functionality

Question

Your challenge today is to implement a t9-like functionality.

You will implement a function that will only have 2 parameters.
You will receive 1 phone number in a string and the content of a text file with a list of words (don't assume a specific newline style).
You can use the link https://raw.githubusercontent.com/eneko/data-repository/master/data/words.txt to test the functionality, or use /usr/share/dict/words (check A text file with a list of words [closed] for more information).

You can assume that you will always receive at least 2 numbers.

Given the number, you will read from a list of words and returns the words starting with the letters mapping to those words. This means that the input should be only numbers from 2 to 9.
You can do whatever you want if you receive invalid input.

If no match is found, you can return an empty list, null/nil or 0.

Remember that the cellphone keys are mapped to their equivalent chars:

• 0 and 1 are invalid
• 2 matches [abc]
• 3 matched [def]
• 4 matches [ghi]
• 5 matches [jkl]
• 6 matches [mno]
• 7 matches [pqrs]
• 8 matches [tuv]
• and 9 matches [wxyz]

Examples:

f('52726')
//returns ["Japan","japan","Japanee","Japanese","Japanesque"...,"larbowlines"]

f('552')
//returns ["Kjeldahl","kjeldahlization","kjeldahlize"...,"Lleu","Llew"]

f('1234')
//makes demons fly out your nose or divide by 0

f('9999')
//returns ["Zyzzogeton"]

f('999999')
//returns [] or null/nil or 0

After you run your function, you can print it in any way you wish.

Rules:

• Standard loopholes are INVALID
• You must return something, even if it is null/nil
  Javascript will return undefined if you don't return something, therefore this rule.
• You cannot use or re-implement other's answers or copy my implementation.
• You can assume, for Javascript, that the browser will be already opened and that the innerText/textContent of the automatic element will be passed as the 2nd parameter
• For compiled languages, you cannot pass special arguments to the compiler
• You can receive the file name over compiler arguments
• Variables, macros, global variables, constants, non-standard classes and all the sort passing other values inside the function will be considered invalid.
• In Javascript, variables without the keyword var render your code invalid
• Your function will be named f
• You can only and only have 2 arguments on your function
• Try to keep your code under 500 seconds to run.
• You don't have to worry about whitespace
• You must use only ASCII printable characters.
  Exceptions are languages that only use non-printable characters (APL and whitespace are 2 examples).

Scoring:

• Lowest number of bytes win
• Having invalid ASCII printable characters in your answer, will count as the answer being encoded in UTF-32
  The exception to the encoding will make your answer be count by characters.
• Only the function body counts, don't count anything else you do outside it
• Bonus of -30% if you make a prediction system based on the neighborhood or most common words
• Bonus of -20% in size if you only return the first 5 matches for each letter corresponding to the first number (e.g.: 245 would returns 5 words starting with 'a', 5 starting with 'b' and 5 starting with 'c').

Here is an example of an implementation, using Javascript:

function f(phone, words)
{
    var keypad=['','','abc','def','ghi','jkl','mno','pqrs','tuv','wxyz'];
    var regex='';

    for(var i=0,l=phone.length;i<l;i++)
    {
        regex+='['+keypad[phone[i]]+']';
    }

    var regexp=new RegExp('\\s('+regex+'[a-z]*)\\s','gi');

    return words.match(regexp);
}

To run it, open the list link and run, for example:

f('9999',document.getElementsByTagName('pre')[0].innerText);
//returns [" Zyzzogeton "]

This example was tested and works under Opera 12.17 64bits on Windows 7 Home Edition 64bits.

Answer 1

CJam, 28 bytes

q~{el{'h-_9/-D+3/}%s1$#!},p;

Takes input in the form of "<number>" [<list of words>]

Example:

"52726" ["Japan" "japan" "Japanee" "Japanese" "Japanesque" "larbowlines" "ablution" "ablutionary" "abluvion" "ably" "abmho" "Abnaki" "abnegate"]

Output:

["Japan" "japan" "Japanee" "Japanese" "Japanesque" "larbowlines"]

Not going for any bonus for now.

Try the code online here but for actual time measurements, run it on the Java compiler

Note that CJam represents empty lists like ""

To convert the raw wordlist into CJam list use the following code with the wordlist as input:

qN/p

Answer 2

Java: 395

This forms a regex pattern based on the letters that are allowed for each number, and then tacks on a .* at the end to match any following characters.

Here is the golfed version:

static ArrayList<String> f(String n,ArrayList<String> d){String[] k={"","","([A-Ca-c])","([D-Fd-f])","([G-Ig-i])","([J-Lj-l])","([M-Om-o])","([P-Sp-s])","([T-Vt-v])","([W-Zw-z])"};String r="";for(int i=0;i<n.length();++i)r+=k[n.charAt(i)-'0'];r += ".*";Pattern p=Pattern.compile(r);ArrayList<String> a=new ArrayList<String>();for(String w:dictionary)if(p.matcher(w).matches())a.add(w);return a;}

And here is the ungolfed version for read-ability

public static ArrayList<String> f(String phoneNumber, ArrayList<String> dictionary) {

    String[] KEY_VALUES = {"", "", "([A-Ca-c])", "([D-Fd-f])", "([G-Ig-i])",
                                            "([J-Lj-l])", "([M-Om-o])", "([P-Sp-s])",
                                            "([T-Vt-v])", "([W-Zw-z])"};

    String regex = "";
    for (int i = 0; i < phoneNumber.length(); ++i) {
        regex += KEY_VALUES[phoneNumber.charAt(i) - '0'];
    }
    regex += ".*";
    Pattern p = Pattern.compile(regex);
    ArrayList<String> answers = new ArrayList<String>();
    for (String word : dictionary) {
        if (p.matcher(word).matches()) {
            answers.add(word);
        }
    }
    return answers;
}

Answer 3

C# .NET 4.5 235

This should work:

IEnumerable<string>F(string n,string d){IEnumerable<string>w=d.Split(null).ToList();string[]a={"","","abc","def","ghi", "jkl","mno","pqrs","tuv","wxyz"};foreach(var i in n){w=w.Where(x=>x.IndexOfAny(a[i-'0'].ToArray())>0);}return w;}

Answer 4

Python 2 (155 bytes)

Should also work in Python 3 with the appropriate replacements (string->bytes, b prefix on strings, etc.).

I wasn't sure if having the maketrans call outside the function is considered "fair"; if not, the function is 134 bytes with it moved inside.

EDIT: Dropped one byte from a stupid oversight.

With prepared maketrans, 67 bytes:

from string import maketrans
t=maketrans('abcdefghijklmnopqrstuvwxyz','22233344455566677778889999')

def f(n,w):
    return[x for x in w.split()if x.lower().translate(t).startswith(n)]

With maketrans in body, 134 bytes:

from string import maketrans

def f(n,w):
    return[x for x in w.split()if x.lower().translate(maketrans('abcdefghijklmnopqrstuvwxyz','22233344455566677778889999')).startswith(n)]

With import and maketrans in body, 155 bytes:

def f(n,w):
    return[x for x in w.split()if x.lower().translate(__import__('string').maketrans('abcdefghijklmnopqrstuvwxyz','22233344455566677778889999')).startswith(n)]

Test call:

print f('9999',open('words.txt','rt').read())

Answer 5

PHP 5.4+ (171 186-20% = 148.8 bytes):

Well, this is quite a huge answer, but well.

I hope this brings more people to answer.

This function expects the raw content being read.

Here is the code:

function f($_,$a){$s=[2=>abc,def,ghi,jkl,mno,pqrs,tuv,wxyz];$a=preg_split('@\r\n|\r|\n@',$a);for($i=0;$c=$_[$i];++$i)foreach($a as$k=>$v)if(!strpos(1..$s[$c],$v[$i])||$t[$v[0]]++>4)unset($a[$k]);return$a;}

This works by verifying that the letter is in the list of allowed letters.

Example: the input 36 would make to check if 1abc has the first letter of the word and that 1def has the 2nd letter.

I append 1 so it doesn't check if the letter is in the 1st position (which would return 0 and that would evaluate to false). if(!strpos(1..$s[$c],$v[$i])) or if(!strpos($c.$s[$c],$v[$i])) will have the same effect, but the 1st confuses more and I like it.

Failing to do so, will remove the word.

With no words left, it returns an empty array.

To test this online, go to http://writecodeonline.com/php/ and create a simple variable with a word for line.

A testable example:

function f($_,$a)
{
    $s=array(2=>abc,def,ghi,jkl,mno,pqrs,tuv,wxyz);
    $a=preg_split('@\r\n|\r|\n@',$a);

    for($i=0;$c=$_[$i];++$i)
        foreach($a as$k=>$v)
            if(!strpos(1..$s[$c],$v[$i]) || $t[$v[0]]++>4)
                unset($a[$k]);
    return$a;
}

$lines=<<<WORDS
one
two
three
four
five
six
seven
eight
nine
ten
WORDS;

var_dump(f('36',$lines));

This should output:

array(1) {
    [3]=>
      string(4) "four"
}

To work on older php versions, replace $s=[2=>abc,def,ghi,jkl,mno,pqrs,tuv,wxyz]; by $s=array(2=>abc,def,ghi,jkl,mno,pqrs,tuv,wxyz);

---

For the 20% bonus:

To reduce the code I simply added ||$t[$v[0]]++>4, which checks how many times the first letter was used.

In php, $t doesn't need to be defined, helping to reduce a big chunk of 37.2 bytes.

To see this effect, use the following variable as the 2nd argument:

$lines=<<<WORDS
one
two
three
four
five
six
seven
eight
nine
ten
twelve
time
tutor
test
truth
WORDS;