Compilare: user.cpp: In function ‘int to_id(int)’: user.cpp:30:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘void afisare()’: user.cpp:47:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<graf[i].size(); j++) ^ user.cpp: In function ‘bool bfs(int, int)’: user.cpp:72:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<graf[crt].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:168:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<graf[crt].size(); j++) ^