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HTML

<a target="_blank" href="http://www.geeksforgeeks.org/write-a-c-program-to-print-all-permutations-of-a-given-string/">Method from here</a>

JavaScript

var input_arr = [1,2,3];
function swap(arr, i, j) {
    if(i != j) {
        var tmp = arr[i];
        arr[i] = arr[j];
        arr[j] = tmp;
    }    
}
function perm(arr, index) {
    if(index == arr.length) {
        console.log(arr);
    } else {
        for(var i = index; i < arr.length; i++) {
            swap(arr, index, i);
            perm(arr, index + 1);
            swap(arr, index, i);
        }
    }
}
perm(input_arr, 0);