#include <bits/stdc++.h>
using namespace std;
const int mx = 1e5+5;
int nxt[mx][26], le[mx];
int main() {
    string s,t;
    cin >> s >> t;
    int n = s.size();
    memset(nxt,-1,sizeof(nxt));
    memset(le,-1,sizeof(le));
    for (int i = 0; i < n; i++) {
        if (i > 0) {
            for (int j = 0; j < 26; j++) {
                nxt[i][j] = nxt[i-1][j];
            }
        }
        nxt[i][s[i]-'a'] = i;
    }
    for (int i = 0; i < n; i++) {
        int cur = i;
        for (int j = t.size()-1; j >= 0; j--) {
            if (cur < 0) {
                break;
            }
            cur = nxt[cur][t[j]-'a'];
            if (j != 0) {
                cur--;
            }
        }
        if (cur >= 0) {
            le[i] = cur;
        }
    }
    long long ans = 0;
    for (int i = 0; i < n; i++) {
        if (le[i] != -1) {
            ans += le[i]+1;
        }
    }
    cout << ans << '\n';
    return 0;
}