Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:16:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[Nod].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:50:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < Sol.size(); ++i) ^ user.cpp:25:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("treespotting.in", "r", stdin); ^ user.cpp:26:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("treespotting.out", "w", stdout); ^ user.cpp:27:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:29:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^ user.cpp:36:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^