Compilare: user.cpp: In function ‘int main()’: user.cpp:23:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<ubu.size()-1;++i) ^ user.cpp: In function ‘void B_F(int)’: user.cpp:65:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();++i) ^ user.cpp: In function ‘void read()’: user.cpp:33:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ubuntzei.in", "rt", stdin); ^ user.cpp:34:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ubuntzei.out", "wt", stdout); ^ user.cpp:36:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &k); ^ user.cpp:40:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &c); ^ user.cpp:46:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &x, &y, &cost); ^