Compilare: main.cpp: In function 'int main()': main.cpp:19:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i<a.size();++i) ~^~~~~~~~~ main.cpp:23:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < a.size() && (gd(a[i]) || a[i] != ' ')) ~~^~~~~~~~~~ main.cpp:2:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] #define FILES freopen("text.in","r",stdin);\ ^ main.cpp:17:5: note: in expansion of macro 'FILES' FILES ^~~~~ main.cpp:3:45: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("text.out","w",stdout); ^ main.cpp:17:5: note: in expansion of macro 'FILES' FILES ^~~~~