Compilare: user.cpp: In function ‘void dfs(int, int, int, int)’: user.cpp:57:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < G[nod].size(); i++) ^ user.cpp: In function ‘void read()’: user.cpp:21:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:25:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp: In function ‘int main()’: user.cpp:77:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbpal.in", "r", stdin); ^ user.cpp:78:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arbpal.out", "w", stdout); ^