package com.company;

import java.nio.charset.StandardCharsets;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        /*Scanner scanner = new Scanner(System.in, StandardCharsets.US_ASCII);
        int billTotal = 0;
        String input = "";

        while (scanner.hasNextLine()){
            input = scanner.nextLine();
            if(input.startsWith("|"))
                billTotal += 42 * input.length();
            else{
                String[] ordrinaryBill = input.split(",-");
                int price = Integer.parseInt(ordrinaryBill[0]);
                billTotal += price * ordrinaryBill[1].length();
            }
        }
        int difference = billTotal % 10;
        if (difference != 0)
            billTotal += 10 - difference;

        String output = String.format("%d,-",billTotal);
        System.out.println(output);*/

        String line1 = "";
        String line2 = "";
        String word1 = "";
        String word2 = "";
        int c = 1;
        int token = 0;

        Scanner scanner = new Scanner(System.in, StandardCharsets.US_ASCII);

        line1 = scanner.nextLine();
        //line1 = System.in.toString();
        line2 = scanner.nextLine();
        //line2 = System.in.toString();

        for (int i = 0; i < line1.length(); i++)
        {
            if(line1.charAt(i) >= '0' && line1.charAt(i) <= '9')
            {
                token++;
                for (int j = 0; j < (line1.charAt(i) - '0'); j++)
                    word1 += " ";
            }
            else
                word1 += line1.charAt(i);
        }

        for (int i = 0; i < line2.length(); i++)
        {
            if(line2.charAt(i) >= '0' && line2.charAt(i) <= '9')
            {
                token++;
                for (int j = 0; j < (line2.charAt(i) - '0'); j++)
                    word2 += " ";
            }
            else
                word2 += line2.charAt(i);
        }

        //System.out.println(word1);
        //System.out.println(word2);


        //int editDistance[word1.length() + 1][word2.length() + 1];
        int[][] editDistance = new int [word1.length() + 1][word2.length() + 1];

        for (int i = 0; i <= word1.length(); i++)
        {
            for (int j = 0; j <= word2.length(); j++)
            {
                if (j == 0)
                    editDistance[i][j] = i;
                else if (i == 0)
                    editDistance[i][j] = j;
                else
                {
                            if ((word1.charAt(i - 1) == ' ' || word2.charAt(j - 1) == ' ') || (word1.charAt(i - 1) == word2.charAt(j - 1)))
                                c = 0;
                            else
                                c = 2;
                        editDistance[i][j] = Math.min(Math.min(editDistance[i - 1][j - 1] + c, editDistance[i - 1][j] + 1), editDistance[i][j - 1] + 1);
                }
            }
        }

        //System.out.println(editDistance[word1.length() ][word2.length() ]);
        System.out.println(editDistance[word1.length() ][word2.length() ] + token);


        }
}