Compilare: user.cpp: In function ‘int main()’: user.cpp:50:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < sol.size(); i++) ^ user.cpp:20:6: warning: unused variable ‘c’ [-Wunused-variable] int c = 0; ^ user.cpp:11:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zeul.in","r",stdin); ^ user.cpp:12:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zeul.out","w",stdout); ^ user.cpp:16:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&a,&b); ^