Character Multiplier

import java.util.Scanner;

public class CharacterMultiplier {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String[] input = scanner.nextLine().split(" +");

        String str1 = input[0].trim();
        String str2 = input[1].trim();

        int sum = 0;

        for (int index = 0; index < Math.max(str1.length(), str2.length()); index++) {
            if (index < str1.length() && index < str2.length()) {
                sum = sum + str1.charAt(index) * str2.charAt(index);
            } else if (index < str1.length()){
                sum += str1.charAt(index);
            } else {
                sum += str2.charAt(index);
            }
        }
        System.out.println(sum);
    }
}