import java.util.Scanner;

public class CharacterMultiplier {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String string1 = scan.nextLine();
        String string2 = scan.nextLine();
        int result = multiplier(string1, string2);
        System.out.println(result);
    }

    public static int multiplier(String string1, String string2) {
        int sum = 0;
        if (string1.length() > string2.length()) {
            for (int i = 0; i < string1.length(); i++) {
                try {
                    sum += string1.charAt(i) * string2.charAt(i);
                } catch (StringIndexOutOfBoundsException e) {
                    sum += string1.charAt(i);
                }
            }
        } else {
            for (int i = 0; i < string2.length(); i++) {
                try {
                    sum += string2.charAt(i) * string1.charAt(i);
                } catch (StringIndexOutOfBoundsException e) {
                    sum += string2.charAt(i);
                }
            }
        }
        return sum;
    }
}