tayfunerbilen/Combinations_Calculator.js

## Combinations_Calculator.js
function factorial(number){
  var value = number;
  for ( var i = number; i > 1; i-- ){
    value *= i - 1;
  }
  return value;
};

function combination(n, r){
  if ( n == r ) return 1;
  return factorial(n) / (factorial(r) * factorial(n - r));
};

// usage
alert( combination(10,5)  ); // 252
	function factorial(number){
	var value = number;
	for ( var i = number; i > 1; i-- ){
	value *= i - 1;
	}
	return value;
	};

	function combination(n, r){
	if ( n == r ) return 1;
	return factorial(n) / (factorial(r) * factorial(n - r));
	};

	// usage
	alert( combination(10,5) ); // 252