#include <bits/stdc++.h> using namespace std; const int MOD = 1000000007; const int MAXN = 2005; long long dp[MAXN][MAXN]={1}; int a[MAXN], b[MAXN]; int main() { int n, m; cin >> n >> m; for (int i = 1; i <= n; i++) { cin >> a[i]; } for (int i = 1; i <= m; i++) { cin >> b[i]; } for (int i = 0; i <= n; i++) { dp[i][0] = 1; } for (int j = 0; j <= m; j++) { dp[0][j] = 1; } for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { if (a[i] == b[j]) { dp[i][j] = (dp[i-1][j-1] + dp[i-1][j] + dp[i][j-1] - 1) % MOD; } else { dp[i][j] = (dp[i-1][j] + dp[i][j-1] - dp[i-1][j-1]) % MOD; } if (dp[i][j] < 0) { dp[i][j] += MAXN; } } } cout << dp[n][m] << endl; return 0; }