Compilare: main.cpp: In function 'int main()': main.cpp:40:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<primes.size() && gc!= 1 && 1LL * primes[i] * primes[i] <= cgc; ++i) ~^~~~~~~~~~~~~~ main.cpp:20:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("eqset.in","r",stdin); ^ main.cpp:21:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("eqset.out","w",stdout); ^ main.cpp:23:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ main.cpp:27:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld",&a,&b); ^