Algorithm for computing partitions of a set of n elements in

function example() {
    var arr = ["A","B","C","D","E","F"];
    combinations2(arr, 3, 0, Array(3));
}

function combinations2(arr, len, startPosition, result) {
    if (len == 0) {
        alert(result);
        return;
    }
    for (i = startPosition; i <= arr.length-len; i++) {
        result[result.length - len] = arr[i];
        combinations2(arr, len-1, i+1, result);
    }
}