Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:12:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<drum[tata].size();i++) ^ user.cpp: In function ‘void rdfs(int)’: user.cpp:26:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<rdrum[tata].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:71:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(x=0;x<comp[i].size();x++) ^ user.cpp:39:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in","r",stdin); ^ user.cpp:40:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out","w",stdout); ^ user.cpp:41:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:44:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^