Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:32:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 0, i; k < G[x].size(); ++k) ^ user.cpp: In function ‘int main()’: user.cpp:17:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("asmax.in", "r", stdin); ^ user.cpp:18:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &N); ^ user.cpp:20:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &C[i]); ^ user.cpp:22:68: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i", &a, &b), G[a].push_back(b), G[b].push_back(a); ^