Compilare: user.cpp: In function ‘int main()’: user.cpp:115:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<ans.size(); i++) ^ user.cpp: In function ‘void build_graph()’: user.cpp:90:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &graf.N); ^ user.cpp:91:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &m); ^ user.cpp:96:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d %d", &a[i], &b[i], &c[i]); ^ user.cpp: In function ‘int main()’: user.cpp:102:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("critice.in", "r", stdin); ^ user.cpp:103:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("critice.out", "w", stdout); ^