代码

#include <algorithm>

int part(unsigned *a, int n){
    int mid = a[n/2], i = -1, j = n;
    while (true)
    {
        do ++i; while (a[i] < mid);
        do --j; while (a[j] > mid);
        if (i >= j) return i;
        std::swap(a[i], a[j]);
    }
}

void sort(unsigned *a, int n) {
    if (n <= 1)
        return;
    int p = part(a, n);
    sort(a, p);
    sort(a + p, n - p);
}

评测结果