Compilare: main.cpp: In function 'int bfs(int)': main.cpp:26:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<a[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp:28:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:39:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<str.size();i++){ ~^~~~~~~~~~~