快速排序

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
    <meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
    <title>Document</title>
<script type="text/javascript">
    function quickSort(arr){
        if(arr.length<=1){
            return arr;
        }

        var num = Math.floor( arr.length/2 );
        var numValue = arr.splice(num,1);
        var left = [];
        var right = [];

        for(var i=0;i<arr.length;i++){
            if(arr[i]<numValue){
                left.push(arr[i]);
            }else{
                right.push(arr[i]);
            }
        }

        return quickSort(left).concat([numValue],quickSort(right));
    }

    alert( quickSort([22,30,15,7,9,44,18]) );
    
</script>
</head>
<body>
    
</body>
</html>

原理就是找到数组的中心点作为基点,把比基点小的都放在左边,大的都放在右边,然后再利用递归即可。

原文地址:https://www.cnblogs.com/toodeep/p/4474304.html