#include <bits/stdc++.h>
using namespace std;
using ll=long long;
using ld=double;
using vll=vector<ll>;
#define FOR(i,a,b) for(ll i=a;i<(ll)b;++i)
#define ROF(i,a,b) for(ll i=a;i>=(ll)b;--i)
#define PB push_back

#define INF (1ll<<61)

string A,B;
ll dp[10001][1001];

ll editDistance(ll a,ll b){
  if(dp[a][b]!=-1)return dp[a][b];
  if(a>=A.size())return dp[a][b]=max(0ll,(ll)B.size()-b); // +-1
  if(b>=B.size())return dp[a][b]=max(0ll,(ll)A.size()-a); // +-1
  ll nothing=INF;
  if (A[a]==B[b])nothing=editDistance(a+1,b+1)-1;
  ll delA=editDistance(a+1,b);
  ll delB=editDistance(a,b+1);
  ll expA=INF;
  if('0'<=A[a]&&A[a]<='9'){
    ll val=A[a]-'0';
    expA=editDistance(a+1,b+val);
  }
  ll expB=INF;
  if('0'<=B[b]&&B[b]<='9'){
    ll val=B[b]-'0';
    expB=editDistance(a+val,b+1);
  }
  return dp[a][b]=1+min(nothing,min(delA,min(delB,min(expA,expB))));
}

int main(){
  ios::sync_with_stdio(0);cin.tie(0);
  cin>>A>>B;
  memset(dp,-1,sizeof dp);
  printf("%lld\n",editDistance(0,0));
  // FOR(i,0,A.size()){FOR(j,0,B.size()){printf("%lld %lld: %lld\n",i,j,dp[i][j]);}puts("");}

  return 0;
}