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#include <iostream>
#include <vector>

using namespace std;

int BM(string s, string t) {
    int n = s.size();
    int m = t.size();
    vector<int> v;
    for (int i = 0; i <= n - m; ++ i) {
        if (s[i] == t[0])
            v.push_back(i);
    }
    for (int i = 0; i < v.size(); ++ i) {
        int j = m - 1;
        while (j >= 0 && s[v[i] + j] == t[j]) j--;
        if (j == -1) return v[i];
    }
    return -1;
}

int main() {
    string s, t;
    cin >> s >> t;
    cout << BM(s, t) << endl;
    return 0;
}