#include<iostream>
#include<string>

using namespace std;

int dp[11111][2222];

string s, r;
string ss, rr;

int main()
{
	int ans = 0;
	cin>>r>>s;
	for(int i = 0; i < s.size(); i++)
	{
		if(s[i] >= 'a' && s[i] <= 'z')
			ss += s[i];
		else
		{
			ans++;
			for(int j = 0; j < s[i]-'0'; j++)
				ss+=' ';
		}
	}
	for(int i = 0; i < r.size(); i++)
	{
		if(r[i] >= 'a' && r[i] <= 'z')
			rr += r[i];
		else
		{
			ans++;
			for(int j = 0; j < r[i]-'0'; j++)
				rr+=' ';
		}
	}
	for(int i = 0; i <= ss.size(); i++)
		dp[i][0] = i;
	for(int i = 0; i <= rr.size(); i++)
		dp[0][i] = i;
	for(int i = 1; i <= ss.size(); i++)
	{
		for(int j = 1; j <= rr.size(); j++)
		{
			if(ss[i] == rr[j] || ss[i] == ' ' || rr[j] == ' ')
				dp[i][j] = dp[i-1][j-1];
			else
				dp[i][j] = min(dp[i-1][j], dp[i][j-1])+1;
		}
	}
	cout<<ans+dp[ss.size()][rr.size()]<<endl;
	return 0;
}