#include<iostream> #include<cmath> using namespace std; int n,q,book[6666],len[6666],num[6666]; int main() { cin>>n>>q; for(int i=1; i<=n; i++) cin>>book[i]; for(int i=1; i<=q; i++) { cin>>len[i]>>num[i]; int tmp = pow(10,len[i]),min = 10000001; for(int j=1; j<=n; j++) if(book[j] % tmp == num[i] && book[j] < min) min = book[j]; if(min != 10000001) cout<<min<<endl; else cout<<-1<<endl; } return 0; }