Java快速排序的方法有哪些

164次閱讀

共計 1018 個字符，預計需要花費 3 分鐘才能閱讀完成。

Java 中常用的快速排序方法有以下幾種：

使用遞歸實現的快速排序方法：

public void quickSort(int[] arr, int low, int high) {if (low < high) {int pivot = partition(arr, low, high);
        quickSort(arr, low, pivot - 1);
        quickSort(arr, pivot + 1, high);
    }
}

public int partition(int[] arr, int low, int high) {int pivot = arr[high];
    int i = low - 1;
    for (int j = low; j < high; j++) {if (arr[j] < pivot) {
            i++;
            int temp = arr[i];
            arr[i] = arr[j];
            arr[j] = temp;
        }
    }
    int temp = arr[i + 1];
    arr[i + 1] = arr[high];
    arr[high] = temp;
    return i + 1;
}

使用棧實現的非遞歸快速排序方法：

public void quickSort(int[] arr, int low, int high) {Stack<Integer> stack = new Stack<>();
    stack.push(low);
    stack.push(high);

    while (!stack.isEmpty()) {high = stack.pop();
        low = stack.pop();
        int pivot = partition(arr, low, high);

        if (pivot - 1 > low) {stack.push(low);
            stack.push(pivot - 1);
        }
        if (pivot + 1 < high) {stack.push(pivot + 1);
            stack.push(high);
        }
    }
}

public int partition(int[] arr, int low, int high) {int pivot = arr[high];
    int i = low - 1;
    for (int j = low; j < high; j++) {if (arr[j] < pivot) {
            i++;
            int temp = arr[i];
            arr[i] = arr[j];
            arr[j] = temp;
        }
    }
    int temp = arr[i + 1];
    arr[i + 1] = arr[high];
    arr[high] = temp;
    return i + 1;
}