Largest Row in a Tree Solution

largest-level-of-tree.js

var Tree = function(value) {
	this.value = value;
	this.children = [];
}

Tree.prototype.addChild = function(value) {
	this.children.push(new Tree(value));
}

/**
 * Returns the row with the largest sum of datum
 * If theres a tie, return the closest row
 */
Tree.prototype.findLargestLevel = function() {
	var sumsByRow = {};

	var findLargestLevelHelper = function(level, tree) {
		sumsByRow[level] = sumsByRow[level] || 0;
		sumsByRow[level] += tree.value;

		for (var i = 0; i < tree.children.length; i++) {
			findLargestLevelHelper(level + 1, tree.children[i]);
		}
	}

	findLargestLevelHelper(0, this);

	var largestRow = -1;
	var largestValue = -Infinity;

	for (var row in sumsByRow) {
		row = parseInt(row);
		var value = sumsByRow[row];

		if (value > largestValue) {
			largestRow = row;
		}
	}

	return largestRow;
}

/**
 * tests Find Largest Level if its working or not
 */
var testFindLargestLevel = function() {
	console.log('it should find the largest level of a tree');

	var tree = new Tree(5);
	tree.addChild(3);
	tree.addChild(6);
	tree.children[0].addChild(13);
	tree.children[0].addChild(8);
	tree.children[1].addChild(6);

	console.log(tree.findLargestLevel() === 2);
}