Compilare: user.cpp: In function ‘int main()’: user.cpp:27:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1; i<v.size(); i++) ^ user.cpp:8:38: 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:9:40: 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:11:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &a, &b); ^