#include <iostream>
#include <ctime>
using namespace std;
int main() {
clock_t before = clock();
int k = 0;
for (int i = 0; i < 100000; i++) {
k += i;
}
clock_t duration = clock() - before;
cout << "耗时: " << (float)duration / CLOCKS_PER_SEC << " 秒";
return 0;