代码

#include <algorithm>

void sort(unsigned *a, int n) {
    const int ful = (1 << (1 << 4)) - 1;
    n--;
    int tt[ful + 5];
    unsigned tmp[n + 5];
    for (int C = 0; C <= 1; C++) {
        for (int i = 0; i <= ful; i++) tt[i] = 0;
        for (int i = 0; i <= n; i++) ++tt[(a[i] >> (C * 16)) & ful];
        for (int i = 1; i <= ful; i++) tt[i] += tt[i - 1];
        for (int i = n; i >= 0; i--) tmp[--tt[(a[i] >> (C * 16)) & ful]] = a[i];
        for (int i = 0; i <= n; i++) a[i] = tmp[i];
    }
}

评测结果