Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:20:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<G[node].size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:32:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dominouri.in", "r", stdin); ^ user.cpp:33:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dominouri.out", "w", stdout); ^ user.cpp:37:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:40:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:42:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &y); ^ user.cpp:48:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &dominos[i]); ^