Compilare: user.cpp: In function ‘bool try_match(int, int)’: user.cpp:97:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return nr==mar.G[y].size(); ^ user.cpp: In function ‘int main()’: user.cpp:126:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sakura.in","r",stdin); ^ user.cpp:127:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sakura.out","w",stdout); ^ user.cpp:129:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&T); ^ user.cpp: In member function ‘void copacel::grow()’: user.cpp:20:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:25:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^