编一个求质数的程序怎么老弹出一个文件

#include<iostream>#include<bitset>#include<cmath>using namespace std;int main(){const int a(1000);const int b = sqrt(a);bitset<a>num;num.set();num[1] = 0;for (int i = 1; i <= a; i++){for (int j = i * i; j <= b; j+=i){num[j] = 0;}}cout << a<< "有" << num.count() << "质数" << endl;for (int i = 1; i <= a; i++){if (num[i] = 1)cout << i << endl;}return 0;}