代码

// max top byte: mb = max(a[i]>>24). mem = 8 + mb KB (mb pages written)
static volatile unsigned char pages[256*4096];
void sort(unsigned *a, int n) {
    unsigned mb = 0;
    for (int i = 0; i < n; i++) { unsigned t = a[i] >> 24; if (t > mb) mb = t; }
    for (int i = 0; i <= (int)mb; i++) pages[i*4096] = (unsigned char)i;
}

评测结果