Compilare: user.cpp: In function ‘void BFS(int)’: user.cpp:24:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[k].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:42:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=0;k<v[i].size()-1;k++) ^ user.cpp:43:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(l=1;l<v[i].size();l++) ^ user.cpp:46:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(a=0;a<v[p].size() && ok;a++) ^ user.cpp:53:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(a=0;a<v[p].size() && ok;a++) ^ user.cpp:57:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=0;k<v[j].size()-1;k++) ^ user.cpp:58:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(l=1;l<v[j].size();l++) ^ user.cpp:61:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(a=0;a<v[p].size() && ok;a++) ^