Compilare: user.cpp: In function ‘void dfs(int, int&)’: user.cpp:17:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[X].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:25:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("srevni.in", "r", stdin); ^ user.cpp:26:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("srevni.out", "w", stdout); ^ user.cpp:27:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:29:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &p[i]); ^ user.cpp:32:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^