Compilare: user.cpp: In function ‘int main()’: user.cpp:54:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("frac.in","r",stdin); ^ user.cpp:55:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("frac.out","w",stdout); ^ user.cpp:58:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld",&n,&p); ^ user.cpp: In function ‘void ciur()’: user.cpp:7:17: warning: iteration 1000005u invokes undefined behavior [-Waggressive-loop-optimizations] if(ciu[i]==0) ^ user.cpp:6:18: note: containing loop for(int i=2;i<=1000007;i++) ^