#include<bits/stdc++.h>
using namespace std;
#define int long long
#define f first
#define s second
#define mp make_pair
#define eb emplace_back
#define pb push_back
typedef pair<int,int> pii;

const int mxn=2e4+2;
int dp[mxn][mxn];

int32_t main() {
    ios_base::sync_with_stdio(false);cin.tie(0);
    string s;
    string T;
    cin>>s>>T;

    string t="x";
    t[0]=T[0];

    for(int i=1;i<T.length();i++){
        if(T[i]!=t[t.size()-1]){
            t += T[i];
        }
    }

    int ss=s.length();
    int tt=t.length();

    for(int i=0;i<=ss;i++){
        for(int j=0;j<=tt;j++){
            //length of suffix (in S)
            dp[i][j]=1e9;
        }
    }
    // cout<<t<<'\n';

    s="$"+s;
    t="$"+t;
    
    // dp[0][0]=0;
    for(int i=0;i<=ss;i++){
        dp[i][0]=0;
        for(int j=0;j<=tt;j++){
            // cout<<i<<' '<<j<<' '<<dp[i][j]<<'\n';
            if(i+1<=ss && j+1<=tt && s[i+1]==t[j+1]){
                dp[i+1][j+1]=min(dp[i+1][j+1],dp[i][j]+1);
            }
            if(j+2 <= tt){
                if(s[i-1]==t[j+1] && s[i]==t[j+2]){
                    dp[i][j+2] = min(dp[i][j+2], max(dp[i][j],2ll) );
                }
            }else if(j+1 <= tt){
                if(s[i-1]==t[j+1]){
                    dp[i][j+1] = min(dp[i][j+1], max(dp[i][j],2ll) );
                }
            }
        }
    }
    int ans=0;
    for(int i=1;i<=ss;i++){
        dp[i][tt]=min(dp[i][tt], dp[i-1][tt]+1);
        // cout<<dp[i][tt]<<' ';
        if(dp[i][tt]==1e9)continue;
        ans+=(i-dp[i][tt]+1);
    }
    cout<<ans;
}
/*
ACGCG
CCG

TATCGC
TTCCG
*/