Program to examine whether the pairs and the orders of “{“,”}”,”(“,”)”,”[“,”]” are correct in expression.

balancedParanthesis.js

var balancedParanthesis = function (str) {
	var openParnth = ['[', '{', '('], closedParanth = [']', '}', ')'];
	var stack = [];
	for (var i = 0; i < str.length; i++) {
		if (openParnth.indexOf(str[i]) > -1) {
			stack.push(str[i]);
		}
		if (closedParanth.indexOf(str[i]) > -1) {
			var lastP = stack.pop();
			var lastPIdx = openParnth.indexOf(lastP)
			if(lastPIdx > -1 && lastPIdx != closedParanth.indexOf(str[i])) return false;
		}
    }
	return stack.length ? false: true;
}

// Test with:
var str = "[()]{}{[()()]()}"; 
balancedParanthesis(str);