代码

#include <algorithm>
#include <random>

const int n = 10000;
int arr[n];

int plus(int a, int b)
{
	for (int i = 0; i < n; i++) {
		arr[i] = i;
	}
	std::random_device rd;
	std::mt19937 gen(rd());
	std::shuffle(arr, arr + n, gen);

	return a % b;
}

评测结果