findCommonAncestor.js

findCommonAncestor.js

// Name == ionox0

process.stdin.resume();
process.stdin.setEncoding("ascii");
var input = '';
process.stdin.on("data", function(chunk){
	input += chunk;
});
process.stdin.on("end", function(){
	findAntecedent(input);
});

function findAntecedent(input){
	input = input.trim();
	var lines = input.split('\n');
	for (var i = 1; i < lines.length - 1; i++){
		lines[i] = lines[i].split(',');
	}
	var p1 = lines[lines.length - 1].split(',')[0];
	var p2 = lines[lines.length - 1].split(',')[1];
	var p1Parents = [];
	while (p1){
		p1Parents.push(p1);
		p1 = findParent(lines, p1);
	}
	while (p2){
		if (p1Parents.indexOf(p2) != -1){
			console.log(p2);
			return;
		}
		p2 = findParent(lines, p2);
	}
}

function findParent(lines, child){
	for (var i = 1; i < lines.length - 1; i++){
		if (lines[i].indexOf(child) != -1 && lines[i][0] != child){
			return lines[i][0];
		}
	}
	return null;
}