Compilare: user.cpp: In function ‘int main()’: user.cpp:55:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j<=v[i].size()-1) ^ user.cpp:59:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=lastchose+1;j<=v[i].size()-1;j++) ^ user.cpp:23:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc3.in", "r", stdin); ^ user.cpp:24:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc3.out", "w", stdout); ^