Compilare: user.cpp: In function ‘int main()’: user.cpp:23:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<v.size();i++) ^ user.cpp:25:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<v.size();i++) ^ user.cpp:10:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("difprim.in","r",stdin); ^ user.cpp:11:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("difprim.out","w",stdout); ^ user.cpp:13:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld%ld",&a,&b); ^