// Hoang Son WIBU lolicon codeforces rate 1439 khong cay #include <bits/stdc++.h> #define F first #define S second #define times double stime = clock(); #define gettime cerr << "\nTime executed: " << (clock() - stime) / CLOCKS_PER_SEC * 1000 << "ms.\n"; using namespace std; typedef long long ll; typedef double dou; typedef long double ldou; typedef pair<int, int> pii; typedef vector<int> vi; typedef vector<vi> vvi; const ll mod = 1000000007; // 998244353 //-std=gnu++17 -Wall int T; string s, t; ll dp[2005][2005]; void process() { // cin >> T; T = 1; while (T--) { cin >> s >> t; for (int i = 1; i <= s.size(); i++) { for (int j = 1; j <= t.size(); j++) { if (s[i - 1] == t[j - 1]) { dp[i][j] = (dp[i - 1][j - 1] + 1) % mod; } dp[i][j] += (dp[i - 1][j] + dp[i][j - 1] - dp[i - 1][j - 1] + mod) % mod; } } cout << dp[s.size()][t.size()]; } } int online = 2; int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); if (online == 0) { freopen("in.inp", "r", stdin); freopen("out.out", "w", stdout); } else if (online == 1) { freopen(".inp", "r", stdin); freopen(".out", "w", stdout); } // times process(); // gettime return 0; }