longestWord.js

function longerThan(word1, word2) {
    if (word2.length > word1.length) {
        return word2;
    } else {
        return word1;
    }
}

function reduce(array, f, acc) {
    var start = acc;
    for(var i = 0; i < array.length; i++) {
        start = f(start, array[i]);
    }
    return start;
}

function map(array, f) {
    var temp = [];
    for(var i = 0; i < array.length; i++) {
        temp.push(f(array[i]));
    }
    return temp;
}

map([1,2,3,4,5], function(x) { return x * x;});

function longestWord(sentence) {
    var words = sentence.split(" ");
    return reduce(words, longerThan, words[0]);
}

longestWord("the quick brown fox jumped over the lazy dog");