word-separator.js

#!/usr/bin/env node

/*=========================================================
Break up a string of words with no spaces into a string of words with appropriate spaces.
=========================================================*/

var dictionary = {
	'the' : 0,
	'a' : 0,
	'may' : 0,
	'be' : 0,
	'maybe' : 0
};

/* ===============================================================
@input: String with no spaces…
@return: String with appropriate spaces added!
Assumption is that all words in the input are dictionary words.
=============================================================== */
var breakUp = function(input) {

	if (input === undefined || input === null || input === "") {
		return "";
	}

	var answer = [];
	var startPos = 0;

	for ( var idx = 1; idx <= input.length; ++idx ) {

		var word = input.substring(startPos, idx);

		if (word in dictionary) {
			answer.push(word);
			startPos = idx;
		}
	}
	return answer.join(" ");
};

/* ===============================================================
 * Unit tests.  Normally I would do this in jasmine.
=============================================================== */
console.log(breakUp("athemaybe") === "a the may be");
console.log(breakUp("a") === "a");
console.log(breakUp("") === "");
console.log(breakUp("maybe") === "may be");
console.log(breakUp("maythemaybebe") === "may the may be be");