sdgsdfgsdg

gistfile1.js

var LETTERS = 'acdegilmnoprstuw';

/**
 * The provided hash function with additional logging
 * @param s
 * @returns {number}
 */
function hash(s) {
    var h = 7;
    for (var i = 0; i < s.length; i++) {
        var s2 = s[i];
        var l = LETTERS.indexOf(s2);
        console.log(h + ' * ' + 37 + ' + ' + l);
        h = (h * 37 + l);
    }
    return h;
}

/*
    7 * 37 + 6
    265 * 37 + 3
    9808 * 37 + 3
    362899 * 37 + 10
    13427273 * 37 + 0
    496809101 * 37 + 2
    18381936739 * 37 + 4
    680131659347
 */
console.log(hash('leepadg'));

/*
    Working backwards from the above:
        - Need to get 4 from: 680131659347 / 37 = 18381936739.10811
        - (680131659347 / 37 + 4) / 37 = 680131659347 + 4/37
        - Therefore 4/37 * 37 would get the index back
        - There are 16 letters therefore decimal places will never be above 16/37
        - We can get the index by multiplying the decimal place by 37!
 */

/**
 * The reverse of the above hash
 * @param n
 * @returns {string}
 */
function reverse(n) {
    var str = '';
    while (n - 37 > 0) {
        var f = n / 37,
            decimalPart = f % 1,
            idx = Math.round(37 * decimalPart),
            char = LETTERS[idx];
        n = f - decimalPart;
        str = char + str;
    }
    return str;
}

console.log(reverse(680131659347)); // leepadg
console.log(reverse(956446786872726)); // trellises