import java.io.PrintStream;
import java.util.Scanner;


public class Y432 {
	Y432() throws Exception {
		Scanner in = new Scanner(System.in);
		PrintStream out = new PrintStream(System.out);
		
		int t = in.nextInt();
		
		for (int tt = 0; tt < t; tt++) {
			char[] s = in.next().toCharArray();
			int n = s.length;
			for (int i=n; i>1; i--) {
				for (int j=0; j < i - 1; j++) {
					int g = (int)s[j] - (int)'0' + (int)s[j+1] - (int)'0';
					g = g / 10 + g % 10;
					s[j] = (char)(g + '0');
				}
			}
			out.println(s[0]);
		}

	}

	public static void main(String argv[]) throws Exception {
		new Y432();
	}
}