Compilare: user.cpp: In function ‘bool ver(int)’: user.cpp:27:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[ ng ].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:51:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("transport2.in", "r", stdin); ^ user.cpp:52:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("transport2.out", "w", stdout); ^ user.cpp:53:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n , &m); ^ user.cpp:58:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x , &y, &z); ^