#include<iostream>
using namespace std;
void zhuan(int n,int b){
if (n>0){
zhuan(n/b,b);
if (n%b<10) cout<<n%b;
else cout<<char(n%b+'A'-10);
}
}
int main(){
int t,n,b;
cin>>t;
for (int i=1; i<=t; i++){
cin>>n>>b;
if (b==16) cout<<"0X";
if (n==0){
cout<<0<<endl;
continue;
}
zhuan(n,b);
cout<<endl;
}
return 0;
}
/**************************************************************
Problem: 2065
User: admin
Language: C++
Result: Accepted
Time:17 ms
Memory:2072 kb
****************************************************************/