#include <bits/stdc++.h>

using namespace std;
int c1[]={0,7,4,1,8,5,2,9,6,3};
int c2[]={0,1,5,2,8,3,9,2,8,7};
int main()
{
    ifstream cin("cifra.in");
    ofstream cout("cifra.out");
    string s;
    int t;
    cin>>t;
    for(int k=1; k<=t; k++)
    {
        cin>>s;
        int n=0,l=s.size()-1;
        if(l>=1)
        {
            int y=s[l-1]-'0';
            n+=c1[y];
        }
        int x=s[l]-'0';
        cout<<(n+c2[x])%10<<"\n";
    }
    return 0;
}