Compilare: user.cpp: In function ‘void Solve()’: user.cpp:68:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < G[x].size() ; i ++ ) ^ user.cpp: In function ‘int scan()’: user.cpp:29:47: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, DIM, stdin), poz = 0; ^ user.cpp:34:47: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf, 1, DIM, stdin), poz = 0; ^ user.cpp: In function ‘void Read()’: user.cpp:43:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &n , &m ); ^ user.cpp: In function ‘int main()’: user.cpp:87:27: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen (IN,"r",stdin); ^ user.cpp:88:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen (OUT,"w",stdout); ^