Compilare: user.cpp: In function ‘void BFS1(int, int&)’: user.cpp:33:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<G[x].size(); i++) ^ user.cpp: In function ‘void BFS2(int, int&)’: user.cpp:51:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<G[x].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:73:13: warning: unused variable ‘i’ [-Wunused-variable] int a,b,i, nod1,nod2; ^