Compilare: main.cpp: In function 'void dfs(int)': main.cpp:22:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<A[nod].size(); i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void read()': main.cpp:11:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ main.cpp:15:22: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ main.cpp: In function 'int main()': main.cpp:42:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dfs.in","r",stdin); ^ main.cpp:43:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dfs.out","w",stdout); ^