代码

void quicksort(unsigned *a, int left, int right) {
    if (left >= right) return;

    unsigned pivot = a[(left + right + 1) >> 1];
    int l = left - 1, r = right + 1;
    while (true) {
        do l++; while (a[l] < pivot);
        do r--; while (a[r] > pivot);
        if (l >= r) break;
        swap(a[l], a[r]);
    }
    quicksort(a, left, l);
    quicksort(a, l + 1, right);

}

void sort(unsigned *a, int n) {
    quicksort(a, 0, n - 1);
}

评测结果