American Soundex

For each line of the input, print it’s American Soundex. Soundex is an algorithm invented by Robert C. Russell and Margaret King Odell to try to find words that sound similar when spoken in a typical American accent. It’s not very good at it’s task but should be an interesting algorithm to golf.

The american soundex is computed as follows, quoted from Wikipedia:

• Save the first letter. Map all occurrences of a, e, i, o, u, y, h, w. to zero(0)
• Replace all consonants (include the first letter) with digits as in below:
  • b, f, p, v → 1
  • c, g, j, k, q, s, x, z → 2
  • d, t → 3
  • l → 4
  • m, n → 5
  • r → 6
• Replace all adjacent same digits with one digit, and then remove all the zero (0) digits
• If the saved letter’s digit is the same as the resulting first digit, remove the digit (keep the letter).

Normally, there is a padding and truncation step but we’ll skip it for this challenge, so the output may come out to be any length.

All words will consist only of ASCII letters, there will be no spaces or other punctuation.

Please suggest more test cases in the Discord.

Judge

(async function*(context: Context): Challenge {

  // Automatically shuffle and deal test cases over multiple runs
  for await (const  value of context.runTestCases(
    [
        ['Rupert', 'R163'],
		['Tymczak', 'T522'],
		['Ruppert', 'R163'],
		['Pfister', 'P236'],
		['Goliath', 'G43'],
		['Minimocha', 'M552'],
		['Bealzebub', 'B4211'],
		['Osterupidosis', 'O2361322'],
		['Claustrophobia', 'C423611'],
		['Bee', 'B'],
		['Computer', 'C5136'],
		['Assasin', 'A225'],
		['Beeswax', 'B22'],
		['Sissigy', 'S22'],
		['Orient', 'O653'],
		['Galaxy', 'G42'],
		['Coding', 'C352'],
		['Smartphone', 'S56315'],
		['Grey', 'G6'],
		['Alphabetical', 'A411324'],
		['Egalitarian', 'E24365'],
		['Sophomore', 'S156'],
		['Leyland', 'L453'],
		['Width', 'W3'],
		['Whale', 'W4'],
		['Spender', 'S1536'],
		['Idol', 'I34'],
		['Quasiadjective', 'Q232231']
    ].map(
      ([i,j]) => {
        return [
          i.replace(/./g,(k)=>Math.random()>0.5?k.toUpperCase():k.toLowerCase()),
          j
        ]
      }
    )
  )) {
    yield value;
  }
  return context.noFailures();
})

Example Code

function soundex(name)
{
    let s = [];
    let si = 1;
    let c;

    //              ABCDEFGHIJKLMNOPQRSTUVWXYZ
    let mappings = "01230120022455012623010202";

    s[0] = name[0].toUpperCase();
    s0_map = mappings[s[0].charCodeAt(0)-65]

    for(let i = 1, l = name.length; i < l; i++)
    {
        c = (name[i].toUpperCase()).charCodeAt(0) - 65;

        if (
          (s.length > 1 && mappings[c] != s[si-1]) ||
          (s.length === 1 && mappings[c] != s0_map)
        )
        {
                    s[si] = mappings[c];
                    si++;
        }
    }

    return s.join("").replace(/0/g,'');
}

process.stdin.on('data', (d)=>{
    k=(''+d).split('\n');
    k.forEach(m=>console.log(soundex(m)))
})