permutation

permutation.js

// pure js version of http://qiita.com/higuma/items/5af4e62bdf4df42ce673

function perm(result, l, r, n){
	if(n > 0){
		r.forEach(function(item, i){
			var rest = r.slice(0); 
			var e = rest.splice(i, 1);
			perm(result, l.concat(e), rest, n - 1);
		})
	}else{
		result.push(l);
	}
}

function perm2(list){
	var result = [];
	perm(result, [], list, list.length);
	return result;
}