Compilare: main.cpp: In function 'void dfs(int)': main.cpp:11:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();++i) ~^~~~~~~~~~~~~~ main.cpp: In function 'void solve(int)': main.cpp:31:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[nod].size();++i) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:55:12: warning: array subscript has type 'char' [-Wchar-subscripts] v[a].push_back(b); ^