下次建议出个计算量较大的题,普通算法1ms就算出来了
[C++] 纯文本查看 复制代码 #include <iostream>
#include <cstdio>
using namespace std;
bool IsPrime(int n)
{
if (n == 2) return true;
if (n % 2 == 0) return false;
for (int i = 3; i * i <= n; i++) {
if (n % i == 0) return false;
}
return true;
}
int main() {
clock_t start = clock();
for (int i = 9999; i >= 2; i -= 2) {
if (IsPrime(i)) {
cout << i << endl;
break;
}
}
cout << "Time: " << clock() - start << "ms" << endl;
return 0;
}
答案:9973 |