All files / algorithms/shuffle/src shuffle.ts

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import { random } from "jga-algorithms-random";
 
// Fisher–Yates algorithm
export const shuffle = <T>(array: T[]): T[] => {
    let currentIndex: number = array.length;
    let temporaryValue: T;
    let randomIndex: number;
 
    // While there remain elements to shuffle...
    while (0 !== currentIndex) {
        // Pick a remaining element...
        randomIndex = random(0, currentIndex);
        currentIndex -= 1;
 
        // And swap it with the current element.
        temporaryValue = array[currentIndex];
        array[currentIndex] = array[randomIndex];
        array[randomIndex] = temporaryValue;
    }
 
    return array;
};