fib.js

function fib_recursive(n) {
	if (n <= 1)
		return n;
	return fib_recursive(n - 1) + fib_recursive(n - 2);
}

var fib = new Object();

fib.recursive = function(n) {
	if (n <= 1)
		return n;
	return this.recursive(n - 1) + this.recursive(n - 2);
}

fib.iterative = function(n) {
	var a = 0;
	var b = 1;
	var c = 0;
	for (i = 0; i < n; i++) {
		c = a + b;
		a = b;
		b = c;
	}
	return a;
}