#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define M 1000000007
int sumofdigits(ll x)
{
    int sum=0;
    while(x)
    {
        sum+= x%10;
        x/=10;
    }
    return sum;
}
int F(ll x)
{
    if(x<10){
        return x;
    }
    else{
        return F(sumofdigits(x));
    }
}
int solve(ll a,ll n)
{
    ll res=1;
    while(n)
    {
        if(n%2==1){
            res=res*F(a);
            res=F(res);
        }
        a=F(F(a)*F(a));
        n/=2;
    }
    return res;
}
int main()
{
    //freopen("test1.txt","r",stdin);
    //freopen("file1.txt","w",stdout);
    int t;
    ll a,n;
    cin>>t;
    while(t--)
    {
        cin>>a>>n;
        cout<<solve(a,n)<<endl;
    }
}