import java.util.*;

public class Main {
    private static Scanner sc = new Scanner(System.in);
    public static void main(String[] args) throws Exception {
        int n = sc.nextInt();
        for (int i = 0;i < n;i++) {
            solve(sc.next());
        }
    }
    
    public static void solve(String s) {
        while (s.length() != 1) {
            StringBuilder sb = new StringBuilder();
            for (int i = 0;i < s.length()-1;i++) {
                int sum = Integer.valueOf(s.substring(i, i+1)) + Integer.valueOf(s.substring(i+1, i+2));
                if (sum >= 10) sum -= 9;
                sb.append(sum);
            }
            s = sb.toString();
        }
        System.out.println(s);
    }
}