Compilare: user.cpp: In function ‘int main()’: user.cpp:29:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a.size();i++) ~^~~~~~~~~ user.cpp:38:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz==b.size()) ~~~^~~~~~~~~~ user.cpp:42:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz==b.size()) ~~~^~~~~~~~~~ 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("balbaiala.in","r",stdin); ^ user.cpp:12:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("balbaiala.out","w",stdout); ^