count_number_of_words_per_sentence.js

// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');

function solution(S) {
    
    // If there are no sentences get out quick.
    if(S.length <= 0){
        return 0;    
    }
    
    // Split the sentence up over ., !, or ?.
    var sentences = S.split(/[.!?]/);
    
    // If the sentences are
    if (sentences.length === 1){
        return sentences.length;
    }

    // Split up the sentences into words.
    sentences.forEach(function(sentence, index) {
        var words = sentence.split(' ');
        
        // Clean up the words array (get rid of the junk "words").
        words.forEach(function(word){
            word = word.trim();
            if(word.match(/\s+/g) || word.length <= 0 || word.match(/\n+/g)){
                words.splice(words.indexOf(word), 1);
            }
        });
        sentences[index] = words; // re-assign the words.
    });
    
    // Get the count of the sentences.
    var max = 0;
    sentences.forEach(function(sentence) {
        if(sentence.length >= max){
            max = sentence.length;
        } 
    });
    
    return max;
}