JavaScriptAlgorithms/Sort/Quick Sort.html at master · biaodigit/JavaScriptAlgorithms · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="SortTestHelper.js"></script>
</head>
<body>
<script>
    function quickSort(arr) {
        let len = arr.length
        _quickSort(arr, 0, len - 1)
        console.log(arr)
    }

    function _partition(arr, l, r) {
        let v = arr[l],
            j = l;
        for (let i = l + 1; i <= r; i++) {
            if (arr[i] < v) {
                swap(arr, i, ++j)
            }
        }
        swap(arr, l, j)
        return j
    }

    /**
     * 递归方式
     * @param arr
     * @param l
     * @param r
     * @private
     */
    function _quickSort(arr, l, r) {
        if (l >= r) {
            return
        }
        let p = _partition(arr, l, r);
        _quickSort(arr, l, p - 1);
        _quickSort(arr, p + 1, r);
    }

    quickSort([3, 1, 5, 7, 2, 4, 9, 6, 10, 8]);

    /**
     * 非递归方式
     * @param arr
     * @param l
     * @param r
     * @private
     */
    function nonRecQuickSort(arr) {
        let stack = [],
            start = 0,
            end = arr.length - 1;
        if (start < end) {
            stack.push(end)
            stack.push(start)
            while (stack.length) {
                let l = stack.pop()
                let r = stack.pop()
                let index = _partition(arr, l, r);
                if (r > index + 1) {
                    stack.push(r)
                    stack.push(index + 1)
                    console.log(stack)
                }
                if (l < index - 1) {
                    stack.push(index - 1)
                    stack.push(l)
                }
            }
        }
        return arr
    }

    function partition(arr, l, r) {
        let v = arr[l]
        while (l < r) {
            while (l < r && arr[r] >= v) {
                r--
            }
            arr[l] = arr[r]
            while (l < r && arr[l] <= v) {
                l++
            }
            arr[r] = arr[l]
        }
        arr[l] = v
        return l
    }
</script>
</body>
</html>