代码

void swap(unsigned *a, unsigned *b)
{
	unsigned t = *a; *a = *b; *b = t;
}

unsigned output[100000000], mx = 0, sta[10]; 

void sort(unsigned *a, int n)
{
	for(unsigned i = 0; i < n; i ++)
		mx = (mx < a[i]) ? a[i] : mx;
	for(unsigned x = 1; mx > 0; mx /= 10, x *= 10)
	{
		memset(sta, 0, sizeof(sta));
		for(unsigned i = 0; i < n; i ++)
			sta[(a[i] / x) % 10] ++;
		for(unsigned i = 1; i < 10; i ++)
			sta[i] += sta[i - 1];
		for(unsigned i = n - 1; i >= 0; i --)
			output[sta[(a[i] / x) % 10] - 1] = a[i], sta[(a[i] / x) % 10] --;
		for(unsigned i = 0; i < n; i ++)
			a[i] = output[i];
	}
}

评测结果