elrasguno · April 5, 2011 15:08
diff --git a/index.html b/index.html
 <!DOCTYPE html>
 <html>
 <head>
 	<script type="text/javascript" src="./interview_hello.js"></script>
 </head>
 <body>
 </body>
 </html>
diff --git a/interview_hello.js b/interview_hello.js
 var InterviewHello = function() {
 	Array.prototype.sum = function() { 
 		var sum = 0; 
 		this.forEach(function(v) { 
 			sum += v; 
 		}); 
 	return sum; 
 	};

 	/***
 	 * do N integers in an array add up to X? 
 	 * @param {int|null}   rX integer to look for
 	 * @param {int|null}   rN number of integers to add up to rX
 	 * @param {int|null}   rListSize length of array to be generated
 	 * @param {array|null} rList list to be operated on
 	 **/

 	var nSumToX = function(rX, rN, rListSize, rList) {
 		var vN           = rN || 2,
 			vX           = rX || 42,
 			vListSize    = rListSize || 50,
 			vIterations  = 0,
 			vResultsList = [],
 			vDebug       = (console && false), 
 			i, l; 

 			// Generate a random list of 50 integers.
 			vList = rList || (function() {
 				var vRand, vNeg, i, vResult = [];
 				for (i=0; i < vListSize; i++) {
 					vNeg  = Math.round(Math.random());
 					vRand = Math.floor(Math.random() * 100);
 					vRand = (vNeg ? vRand * -1 : vRand);
 					vResult.push(vRand);
 				}
 				return vResult;
 			})();

 		console.log(vList);

 		/***
 		 * TODO: this is working if the length of vList is big enough, but
 		 *       it's not resetting vSkipIdxHash or vResultsList properly
 		 *       when it fails to find what it's looking for during an interation.
 		 *       I've been looking at it for too long and can't figure it out.
 		 **/
 		var vFindIntsThatSumsToX = function vFindIntsThatSumsToX(rValueToFind, rNum, rSkipIdxHash) {
 			vDebug && console.log('hey', arguments);
 			var vSkipIdxHash = rSkipIdxHash || {}, 
 				vHash        = {},
 				i, l, vCurrVal, vDiffVal;

 			for (i=0, l=vList.length; i < l; i++) {

 				// Count interations for after the fact
 				vIterations++;

 				vCurrVal     = vList[i];
 				vDiffVal     = rValueToFind - vCurrVal;

 				// Don't look at the index of the current i value.
 				if (rSkipIdxHash && rSkipIdxHash[i] !== undefined) {
 					vDebug && console.log('skipping index:', i, vCurrVal);
 					continue;
 				}

 				if (rNum === 2) {
 					// Check hash for "value" from above.
 					if (vHash[vDiffVal] !== undefined) {
 						vResultsList.push(vCurrVal);
 						vResultsList.push(vDiffVal);
 						console.log('vResultsList: ' + vResultsList, vResultsList.sum());
 						console.log('vIterations', vIterations);
 						return true;
 					}

 					// Populate vHash
 					vHash[vCurrVal] = vDiffVal;
 				} else {
 					vSkipIdxHash[i] = vCurrVal;
 					vResultsList.push(vCurrVal);

 					if (vFindIntsThatSumsToX(vDiffVal, rNum - 1, vSkipIdxHash)) {
 						return true;
 					} else {
 						var vTmp = vResultsList.pop();
 						vSkipIdxHash[i] = undefined;
 						vDebug && console.log("FAIL, popped: ", vTmp, i, vCurrVal);
 					}
 				}
 			}
 			
 			return false;
 		};

 		return vFindIntsThatSumsToX(vX, vN);
 	};

 	// hellonnna
 	var getMaxConsecutiveChar = function(rStr) {
 		var vChars = rStr.split(''), 
 			vMaxConsecutive = 1,
 			vResult = 1,
 			vLastChar,
 			i, l;

 		for (i = 0, l = vChars.length; i < l; i++) {
 			if (i === 0) {
 				vLastChar = vChars[i];
 			} else {
 				if (vLastChar === vChars[i]) { 
 					vMaxConsecutive++;
 				} else {
 					vMaxConsecutive = 1;
 				}
 				vResult = Math.max(vMaxConsecutive, vResult);
 				vLastChar = vChars[i];
 			}
 		}

 		return vResult;
 	};

 	// random, weighted selection
 	var getRandomWeightedSelection = function(rListOfWeightedObjects) {
 		var vWeightsSum = 0,
 			vRand,
 			i, j, l;
 		for (i = 0, l = rListOfWeightedObjects.length; i < l; i++)
 		{
 			vWeightsSum += rListOfWeightedObjects[i].weight;	
 		}

 		vRand = Math.floor(Math.random() * vWeightsSum);


 		for (i = 0, j = 0, l = rListOfWeightedObjects.length; i < l; i++)
 		{
 			j += rListOfWeightedObjects[i].weight;
 			if (j > vRand)
 			{
 				return rListOfWeightedObjects[i];
 			}
 		}
 	};

 	// test getRandomWeightedSelection
 	var test_getRandomWeightedSelection = function() {
 		var vData = [{name : 'A', weight: 2}, {name : 'B', weight: 6}], 
 			vResults = [], 
 			vIterations = 100,
 			i, j;

 		for (i = 0; i < vIterations; i++)
 		{
 			for	(j = 0; j < 8; j++)
 			{
 				if (j === 0) vResults.push({'A' : 0, 'B' : 0});	
 				vResults[i][getRandomWeightedSelection(vData).name]++;
 			}
 		}
 	
 		var vNumA = 0, vNumB = 0;
 		for (i = 0, l = vResults.length; i < l; i++)
 		{
 			vNumA += vResults[i]['A'];
 			vNumB += vResults[i]['B'];
 		}

 		return [Math.round(vNumA / vIterations), Math.round(vNumB / vIterations)];

 	};

 	// sub / pub
 	var _handlers = {};
 	var subscribe = function(rTopic, rCallback)
 	{
 		if (!_handlers[rTopic]) _handlers[rTopic] = [];	
 		_handlers[rTopic].push(rCallback);
 	};

 	var publish = function(rTopic)
 	{
 		var i;
 		if (!_handlers[rTopic]) return;

 		for (i = 0; i < _handlers[rTopic].length; i++)
 		{
 			_handlers[rTopic][i](Array.prototype.slice.call(arguments).slice(1));
 		}
 	};

 	// bind
 	var bind = function(rScope, rFuncName)
 	{
 		return function() {
 			return rScope[rFuncName].apply(rScope, arguments);	
 		};
 	};

 	// parse, replace tokens

 	// fibonacci

 	return {
 		getMaxConsecutiveChar : getMaxConsecutiveChar,
 		getRandomWeightedSelection : getRandomWeightedSelection,
 		test_getRandomWeightedSelection : test_getRandomWeightedSelection,
 		subscribe : subscribe,
 		publish : publish,
 		nSumToX : nSumToX
 	}
 }

 this.interview_hello = new InterviewHello();
	<!DOCTYPE html>
	<html>
	<head>
	<script type="text/javascript" src="./interview_hello.js"></script>
	</head>
	<body>
	</body>
	</html>
	var InterviewHello = function() {
	Array.prototype.sum = function() {
	var sum = 0;
	this.forEach(function(v) {
	sum += v;
	});
	return sum;
	};

	/***
	* do N integers in an array add up to X?
	* @param {int\|null} rX integer to look for
	* @param {int\|null} rN number of integers to add up to rX
	* @param {int\|null} rListSize length of array to be generated
	* @param {array\|null} rList list to be operated on
	**/

	var nSumToX = function(rX, rN, rListSize, rList) {
	var vN = rN \|\| 2,
	vX = rX \|\| 42,
	vListSize = rListSize \|\| 50,
	vIterations = 0,
	vResultsList = [],
	vDebug = (console && false),
	i, l;

	// Generate a random list of 50 integers.
	vList = rList \|\| (function() {
	var vRand, vNeg, i, vResult = [];
	for (i=0; i < vListSize; i++) {
	vNeg = Math.round(Math.random());
	vRand = Math.floor(Math.random() * 100);
	vRand = (vNeg ? vRand * -1 : vRand);
	vResult.push(vRand);
	}
	return vResult;
	})();

	console.log(vList);

	/***
	* TODO: this is working if the length of vList is big enough, but
	* it's not resetting vSkipIdxHash or vResultsList properly
	* when it fails to find what it's looking for during an interation.
	* I've been looking at it for too long and can't figure it out.
	**/
	var vFindIntsThatSumsToX = function vFindIntsThatSumsToX(rValueToFind, rNum, rSkipIdxHash) {
	vDebug && console.log('hey', arguments);
	var vSkipIdxHash = rSkipIdxHash \|\| {},
	vHash = {},
	i, l, vCurrVal, vDiffVal;

	for (i=0, l=vList.length; i < l; i++) {

	// Count interations for after the fact
	vIterations++;

	vCurrVal = vList[i];
	vDiffVal = rValueToFind - vCurrVal;

	// Don't look at the index of the current i value.
	if (rSkipIdxHash && rSkipIdxHash[i] !== undefined) {
	vDebug && console.log('skipping index:', i, vCurrVal);
	continue;
	}

	if (rNum === 2) {
	// Check hash for "value" from above.
	if (vHash[vDiffVal] !== undefined) {
	vResultsList.push(vCurrVal);
	vResultsList.push(vDiffVal);
	console.log('vResultsList: ' + vResultsList, vResultsList.sum());
	console.log('vIterations', vIterations);
	return true;
	}

	// Populate vHash
	vHash[vCurrVal] = vDiffVal;
	} else {
	vSkipIdxHash[i] = vCurrVal;
	vResultsList.push(vCurrVal);

	if (vFindIntsThatSumsToX(vDiffVal, rNum - 1, vSkipIdxHash)) {
	return true;
	} else {
	var vTmp = vResultsList.pop();
	vSkipIdxHash[i] = undefined;
	vDebug && console.log("FAIL, popped: ", vTmp, i, vCurrVal);
	}
	}
	}

	return false;
	};

	return vFindIntsThatSumsToX(vX, vN);
	};

	// hellonnna
	var getMaxConsecutiveChar = function(rStr) {
	var vChars = rStr.split(''),
	vMaxConsecutive = 1,
	vResult = 1,
	vLastChar,
	i, l;

	for (i = 0, l = vChars.length; i < l; i++) {
	if (i === 0) {
	vLastChar = vChars[i];
	} else {
	if (vLastChar === vChars[i]) {
	vMaxConsecutive++;
	} else {
	vMaxConsecutive = 1;
	}
	vResult = Math.max(vMaxConsecutive, vResult);
	vLastChar = vChars[i];
	}
	}

	return vResult;
	};

	// random, weighted selection
	var getRandomWeightedSelection = function(rListOfWeightedObjects) {
	var vWeightsSum = 0,
	vRand,
	i, j, l;
	for (i = 0, l = rListOfWeightedObjects.length; i < l; i++)
	{
	vWeightsSum += rListOfWeightedObjects[i].weight;
	}

	vRand = Math.floor(Math.random() * vWeightsSum);


	for (i = 0, j = 0, l = rListOfWeightedObjects.length; i < l; i++)
	{
	j += rListOfWeightedObjects[i].weight;
	if (j > vRand)
	{
	return rListOfWeightedObjects[i];
	}
	}
	};

	// test getRandomWeightedSelection
	var test_getRandomWeightedSelection = function() {
	var vData = [{name : 'A', weight: 2}, {name : 'B', weight: 6}],
	vResults = [],
	vIterations = 100,
	i, j;

	for (i = 0; i < vIterations; i++)
	{
	for (j = 0; j < 8; j++)
	{
	if (j === 0) vResults.push({'A' : 0, 'B' : 0});
	vResults[i][getRandomWeightedSelection(vData).name]++;
	}
	}

	var vNumA = 0, vNumB = 0;
	for (i = 0, l = vResults.length; i < l; i++)
	{
	vNumA += vResults[i]['A'];
	vNumB += vResults[i]['B'];
	}

	return [Math.round(vNumA / vIterations), Math.round(vNumB / vIterations)];

	};

	// sub / pub
	var _handlers = {};
	var subscribe = function(rTopic, rCallback)
	{
	if (!_handlers[rTopic]) _handlers[rTopic] = [];
	_handlers[rTopic].push(rCallback);
	};

	var publish = function(rTopic)
	{
	var i;
	if (!_handlers[rTopic]) return;

	for (i = 0; i < _handlers[rTopic].length; i++)
	{
	_handlers[rTopic][i](Array.prototype.slice.call(arguments).slice(1));
	}
	};

	// bind
	var bind = function(rScope, rFuncName)
	{
	return function() {
	return rScope[rFuncName].apply(rScope, arguments);
	};
	};

	// parse, replace tokens

	// fibonacci

	return {
	getMaxConsecutiveChar : getMaxConsecutiveChar,
	getRandomWeightedSelection : getRandomWeightedSelection,
	test_getRandomWeightedSelection : test_getRandomWeightedSelection,
	subscribe : subscribe,
	publish : publish,
	nSumToX : nSumToX
	}
	}

	this.interview_hello = new InterviewHello();