algorithm-sort/heapSelect.html at master · zyd317/algorithm-sort · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>堆排序</title>
</head>
<body>
<script>
    Array.prototype.heap_sort = function() {
        var arr = this.slice(0);
        function swap(i, j) {
            var tmp = arr[i];
            arr[i] = arr[j];
            arr[j] = tmp;
        }

        function max_heapify(start, end) {
            var dad = start;//父节点
            var son = dad * 2 + 1;//子节点
            if (son >= end)//无右子树
                return;
            if (son + 1 < end && arr[son] < arr[son + 1])
            //选取左右子树最大的
                son++;
            if (arr[dad] <= arr[son]) {
                //父节点小于最大子节点
                //交换父子，并且再次维护堆
                swap(dad, son);
                max_heapify(son, end);
            }
        }

        var len = arr.length;
        //只对非叶子节点进行   父子维护
        for (var i = Math.floor(len / 2) - 1; i >= 0; i--)
            max_heapify(i, len);
        //依次取出每个大根堆的根节点
        for (var i = len - 1; i > 0; i--) {
            swap(0, i);
            max_heapify(0, i);
        }

        return arr;
    };

    console.log([1,5,3,6,2,7,2,7].heap_sort());
</script>
</body>
</html>