/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
        Scanner sc = new Scanner(System.in);
        int T = sc.nextInt();
       	for (int loop = 0; loop < T; loop++) {
			char[] str = sc.next().toCharArray();
			int[] s = new int[str.length];
			for (int i = 0; i < str.length; i++) s[i] = str[i] - '0';
			int N = s.length;
			while (N > 1) {
				for (int i = 0; i < N - 1; i++) {
					s[i] = s[i] + s[i+1];
					if (s[i] >= 10) s[i] = 1 + s[i] % 10;
				}
				N--;
			}
			System.out.println(s[0]);
       	}
	}
}