How to implement sattolo's algorithm

JavaScript, Sattolo, algorithm

Here is a reference implementation for sattolo’s algorithm in JavaScript.

sattoloTry in REPL
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// Variant shuffle of Fischer-yates
// No item will be in its original location, since elements can't be swapped by themselves
function sattolo(array) {
    const len = array.length;
    for (let i = 0; i < len - 1; i++) { // 0 to n -1, exclusive because the last item doesn't need swapping
        let j = Math.floor(Math.random() *  (len-(i+1)))+(i+1); // i+1 to len, exclusive
        const temp = array[i];
        array[i] = array[j];
        array[j] = temp;
    }
    return array;
}