“permutaciones de funciones () kalibrr” Código de respuesta

permutaciones de funciones () kalibrr

var bitmask;
var characters;
var running;
function permutations() {
    var i;
    if(running.length == characters.length) {
        console.log(running.join(''));
    } else {
    for(i=0; i<characters.length; i++) {
            if ( ((bitmask>>i)&1) == 0 ) {
                running.push(characters[i]);
                bitmask |= (1<<i);
                permutations();
                bitmask ^= 1 << i
                running.pop();
            }
        }
    }
}

var input = document.getElementById('stdin').value;
characters = input.split('');
running = [];
bitmask = 0;
permutations()