Compilare: user.cpp: In function ‘short int DFS(int, int)’: user.cpp:12:37: 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:39:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); j++) ^ user.cpp:51:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < G[i].size(); j++) ^ user.cpp:24:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nustiu.in", "rt", stdin); ^ user.cpp:25:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nustiu.out", "wt", stdout); ^ user.cpp:27:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ user.cpp:29:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ user.cpp:34:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &u, &v); ^