blocks|key|656762|text|使用the+modern+version+of+the+Fisher–Yates+shuffle+algorithm|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|656763|/**
+*+Shuffles+array+in+place.
+*+@param+{Array}+a+items+An+array+containing+the+items.
+*/
function+shuffle(a)+{
++++var+j,+x,+i;
++++for+(i+=+a.length+-+1;+i+>+0;+i--)+{
++++++++j+=+Math.floor(Math.random()+*+(i+%2B+1));
++++++++x+=+a[i];
++++++++a[i]+=+a[j];
++++++++a[j]+=+x;
++++}
++++return+a;
}|code-block|syntax|javascript|656764|ES2015+(ES6)版本|656765|/**
+*+Shuffles+array+in+place.+ES6+version
+*+@param+{Array}+a+items+An+array+containing+the+items.
+*/
function+shuffle(a)+{
++++for+(let+i+=+a.length+-+1;+i+>+0;+i--)+{
++++++++const+j+=+Math.floor(Math.random()+*+(i+%2B+1));
++++++++[a[i],+a[j]]+=+[a[j],+a[i]];
++++}
++++return+a;
}|656766|然而，请注意，从2017年10月起，与destructuring+assignment交换变量会导致显著的性能损失。|656767|使用|656768|var+myArray+=+['1','2','3','4','5','6','7','8','9'];
shuffle(myArray);|656769|实现原型|656770|使用Object.defineProperty+(method+taken+from+this+SO+answer)，我们还可以将此函数实现为数组的原型方法，而不会在for+(i+in+arr)等循环中显示它。下面的代码将允许您调用arr.shuffle()来混洗数组arr|style|CODE|656771|Object.defineProperty(Array.prototype,+'shuffle',+{
++++value:+function()+{
++++++++for+(let+i+=+this.length+-+1;+i+>+0;+i--)+{
++++++++++++const+j+=+Math.floor(Math.random()+*+(i+%2B+1));
++++++++++++[this[i],+this[j]]+=+[this[j],+this[i]];
++++++++}
++++++++return+this;
++++}
});|656772|entityMap|0|LINK|mutability|MUTABLE|url|https://en.wikipedia.org/wiki/Fisher%25E2%2580%2593Yates_shuffle#The_modern_algorithm|1|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment#Swapping_variables|2|https://stackoverflow.com/a/30391923/1256925^0|2|1K|0|0|0|0|0|J|O|1|0|0|0|0|2|L|2B|E|38|D|3Q|3|P|W|2|0|0^^$0|@$1|2|3|4|5|6|7|1C|8|@]|9|@$A|1D|B|1E|1|1F]]|C|$]]|$1|D|3|E|5|F|7|1G|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|1H|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|1I|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|1J|8|@]|9|@$A|1K|B|1L|1|1M]]|C|$]]|$1|O|3|P|5|6|7|1N|8|@]|9|@]|C|$]]|$1|Q|3|R|5|F|7|1O|8|@]|9|@]|C|$G|H]]|$1|S|3|T|5|6|7|1P|8|@]|9|@]|C|$]]|$1|U|3|V|5|6|7|1Q|8|@$A|1R|B|1S|W|X]|$A|1T|B|1U|W|X]|$A|1V|B|1W|W|X]|$A|1X|B|1Y|W|X]]|9|@$A|1Z|B|20|1|21]]|C|$]]|$1|Y|3|Z|5|F|7|22|8|@]|9|@]|C|$G|H]]|$1|10|3|-4|5|6|7|23|8|@]|9|@]|C|$]]]|11|$12|$5|13|14|15|C|$16|17]]|18|$5|13|14|15|C|$16|19]]|1A|$5|13|14|15|C|$16|1B]]]]

<p>Use <a href="https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle#The_modern_algorithm" rel="noreferrer">the modern version of the Fisher–Yates shuffle algorithm</a>:</p>

<pre><code>/**
 * Shuffles array in place.
 * @param {Array} a items An array containing the items.
 */
function shuffle(a) {
    var j, x, i;
    for (i = a.length - 1; i &gt; 0; i--) {
        j = Math.floor(Math.random() * (i + 1));
        x = a[i];
        a[i] = a[j];
        a[j] = x;
    }
    return a;
}
</code></pre>

<h2>ES2015 (ES6) version</h2>

<pre><code>/**
 * Shuffles array in place. ES6 version
 * @param {Array} a items An array containing the items.
 */
function shuffle(a) {
    for (let i = a.length - 1; i &gt; 0; i--) {
        const j = Math.floor(Math.random() * (i + 1));
        [a[i], a[j]] = [a[j], a[i]];
    }
    return a;
}
</code></pre>

<p>Note however, that swapping variables with <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment#Swapping_variables" rel="noreferrer">destructuring assignment</a> causes significant performance loss, as of October 2017.</p>

<h2>Use</h2>

<pre><code>var myArray = ['1','2','3','4','5','6','7','8','9'];
shuffle(myArray);
</code></pre>

<h2>Implementing prototype</h2>

<p>Using <code>Object.defineProperty</code> (<a href="https://stackoverflow.com/a/30391923/1256925">method taken from this SO answer</a>) we can also implement this function as a prototype method for arrays, without having it show up in loops such as <code>for (i in arr)</code>. The following will allow you to call <code>arr.shuffle()</code> to shuffle the array <code>arr</code>:</p>

<pre><code>Object.defineProperty(Array.prototype, 'shuffle', {
    value: function() {
        for (let i = this.length - 1; i &gt; 0; i--) {
            const j = Math.floor(Math.random() * (i + 1));
            [this[i], this[j]] = [this[j], this[i]];
        }
        return this;
    }
});
</code></pre>


blocks|key|656806|text|您可以使用Fisher-Yates+Shuffle+(改编自this+site的代码)：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|656807|function+shuffle(array)+{
++++let+counter+=+array.length;

++++//+While+there+are+elements+in+the+array
++++while+(counter+>+0)+{
++++++++//+Pick+a+random+index
++++++++let+index+=+Math.floor(Math.random()+*+counter);

++++++++//+Decrease+counter+by+1
++++++++counter--;

++++++++//+And+swap+the+last+element+with+it
++++++++let+temp+=+array[counter];
++++++++array[counter]+=+array[index];
++++++++array[index]+=+temp;
++++}

++++return+array;
}|code-block|syntax|javascript|656808|entityMap|0|LINK|mutability|MUTABLE|url|https://en.wikipedia.org/wiki/Fisher%25E2%2580%2593Yates_shuffle|1|http://bost.ocks.org/mike/shuffle/^0|5|K|0|U|9|1|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]|$A|W|B|X|1|Y]]|C|$]]|$1|D|3|E|5|F|7|Z|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|10|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]|Q|$5|L|M|N|C|$O|R]]]]

<p>You could use the <a href="https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle" rel="noreferrer">Fisher-Yates Shuffle</a> (code adapted from <a href="http://bost.ocks.org/mike/shuffle/" rel="noreferrer">this site</a>):</p>

<pre><code>function shuffle(array) {
    let counter = array.length;

    // While there are elements in the array
    while (counter &gt; 0) {
        // Pick a random index
        let index = Math.floor(Math.random() * counter);

        // Decrease counter by 1
        counter--;

        // And swap the last element with it
        let temp = array[counter];
        array[counter] = array[index];
        array[index] = temp;
    }

    return array;
}
</code></pre>


<p>I want to shuffle an array of elements in JavaScript like these:</p>

<pre><code>[0, 3, 3] -&gt; [3, 0, 3]
[9, 3, 6, 0, 6] -&gt; [0, 3, 6, 9, 6]
[3, 3, 6, 0, 6] -&gt; [0, 3, 6, 3, 6]
</code></pre>


How can I shuffle an array?

我想在JavaScript中打乱一个元素数组，如下所示：[0, 3, 3] -> [3, 0, 3][9, 3, 6, 0, 6] -> [0, 3, 6, 9, 6][3, 3, 6, 0, 6] -> [0, 3, 6, 3, 6]

问如何对数组进行混洗？
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