Compilare: user.cpp: In function ‘int main()’: user.cpp:18:27: warning: unused variable ‘i’ [-Wunused-variable] long long int a,b,c,d,i,ok=1,ca=0,r; ^ user.cpp:16:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("multiplu.in","r",stdin); ^ user.cpp:17:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("multiplu.out","w",stdout); ^ user.cpp:19:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld %lld",&a,&b); ^