#include <bits/stdc++.h>
using namespace std;
#define int long long
int E(int n,int k,int j,int l){
int ans=0;
while(j>0&&l>0&&k/l==n/j){
L:
k-=k/l*l;
n-=n/j*j;
l/=10;
j/=10;
}
if(j==0||l>0&&k/l>n/j){
return ans;
}
if(l==0){
ans+=n+1;
return ans;
}
ans+=(n/j-(l>0?k/l+1:0))*j;
ans+=n%j+1;
goto L;
}
int F(int k,int l,int o){
int ans=0;
while(true){
if(l==0){
ans+=o*10;
break;
}
ans+=(10-(l>0?k/l+1:0))*o;
k-=k/l*l;
l/=10;
o/=10;
}
return ans;
}
int H(int n,int k){
if(n==0){
return 0;
}
int j=1,o=1;
while(j*10<=n){
j*=10;
o*=10;
o++;
}
int l=1;
while(l*10<=k){
l*=10;
}
return E(n,k,j,l)+F(k,l,o/10);
}
signed main() {
ios::sync_with_stdio(0);
cin.tie(0);
#ifdef CB
freopen("be2.txt","r",stdin);
// freopen("out.txt","w",stdout);
#endif
int T;
cin>>T;
while(T--){
int K,P;
cin>>K>>P;
int l=K,h=1e18;
while(l!=h){
int m=(l+h)/2;
if(m-H(m,K)>=P){
h=m;
}
else{
l=m+1;
}
}
cout<<(h-H(h,K)!=P?0:h)<<'\n';
}
return 0;
}