Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:13:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<G[node].size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:21:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tequila.in", "r", stdin); ^ user.cpp:22:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tequila.out", "w", stdout); ^ user.cpp:27:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &q); ^ user.cpp:29:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &value[i]); ^ user.cpp:32:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:48:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ user.cpp:41:15: warning: ‘start’ may be used uninitialized in this function [-Wmaybe-uninitialized] dfs(start); ^