Compilare: main.cpp: In function 'll dfs(ll)': main.cpp:17:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:43:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<ans.size();i++) ~^~~~~~~~~~~ main.cpp: In function 'void fast()': main.cpp:22:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("berarii2.in","r",stdin); ^ main.cpp:23:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("berarii2.out","w",stdout); ^