_12CharacterMultiplier

import java.util.Scanner;

/**
 * Created by Lili on 10/19/2015.
 */
public class _12CharacterMultiplier {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String[] inputs = scanner.nextLine().trim().split("\\s");
        int sum =0;
        String first = inputs[0];
        String second = inputs[1];

        int maxLength = Math.max(inputs[0].length(),inputs[1].length());
        for (int i = 0; i < maxLength; i++) {
            if (i <= Math.min(inputs[0].length(), inputs[1].length())) {
                sum += (first.charAt(i) * second.charAt(i));
            }
            else if (first.length() > second.length() &&(i>second.length())){
                      sum += first.charAt(i);

            }
            else  if ((first.length() < second.length())&&(i > Math.min(inputs[0].length(), inputs[1].length()))) {
                        sum += second.charAt(i);

            }

        }
        System.out.println(sum);
    }

}