Compilare: user.cpp: In function ‘void bfs(int, int*, int*)’: user.cpp:26:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<a[x].size(); i++) ^ user.cpp:15:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,x,y,st=-1,dr=0; ^ user.cpp: In function ‘int main()’: user.cpp:44:15: warning: unused variable ‘j’ [-Wunused-variable] int x,y,i,j; ^