Compilare: main.cpp: In function 'int dfs(int, int)': main.cpp:15:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[x].size(); i++) ~^~~~~~~~~~~~ main.cpp:22:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:36:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<niv[i].size(); j++) ~^~~~~~~~~~~~~~