#include <cstdint>
#include <iostream>

#define MAX_N 2000
#define MAX_M 2000
#define MOD 1000000007

using namespace std;

namespace mod
{
template <uint_fast64_t mod>
struct Modint
{
private:
    uint_fast64_t val;

public:
    constexpr Modint( const uint_fast64_t val = 0 ) : val( val % mod ) {}

    constexpr uint_fast64_t &value() noexcept { return val; }

    constexpr const uint_fast64_t &value() const noexcept { return val; }

    constexpr Modint operator+( const Modint &rhs ) const noexcept
    {
        return Modint( *this ) += rhs;
    }

    constexpr Modint operator-( const Modint &rhs ) const noexcept
    {
        return Modint( *this ) -= rhs;
    }

    constexpr Modint operator*( const Modint &rhs ) const noexcept
    {
        return Modint( *this ) *= rhs;
    }

    constexpr Modint operator/( const Modint &rhs ) const noexcept
    {
        return Modint( *this ) /= rhs;
    }

    constexpr Modint &operator+=( const Modint &rhs ) noexcept
    {
        val += rhs.val;
        if ( val > mod ) val -= mod;
        return *this;
    }

    constexpr Modint &operator-=( const Modint &rhs ) noexcept
    {
        if ( val < rhs.val ) val += mod;
        val -= rhs.val;
        return *this;
    }

    constexpr Modint &operator*=( const Modint &rhs ) noexcept
    {
        val *= rhs.val;
        val %= mod;
        return *this;
    }

    constexpr Modint &operator/=( const Modint &rhs ) noexcept
    {
        uint_fast64_t a = rhs.val;
        uint_fast64_t b = mod;
        uint_fast64_t x = 1;
        uint_fast64_t y = 0;

        while ( b > 0 )
        {
            uint_fast64_t q = a / b;
            a -= q * b;
            x -= q * y;

            swap( a, b );
            swap( x, y );
        }

        val *= ( x + mod ) % mod;
        val %= mod;

        return *this;
    }

    friend constexpr ostream &operator<<( ostream &o, const Modint &m )
    {
        return ( o << ( m.val ) );
    }

    friend constexpr istream &operator>>( istream &i, Modint &m )
    {
        return ( i >> ( m.val ) );
    }

    Modint pow( int n )
    {
        Modint res = 1;
        Modint a = Modint( *this );

        while ( n != 0 )
        {
            if ( n & 1 ) res *= a;
            a *= a;
            n >>= 1;
        }

        return res;
    }
};

// Modint Womparer

template <uint_fast64_t mod>
inline bool const operator<( const Modint<mod> &l, const Modint<mod> &r )
{
    return l.value() < r.value();
}

template <uint_fast64_t mod>
inline bool operator>( const Modint<mod> &l, const Modint<mod> &r )
{
    return r < l;
}

template <uint_fast64_t mod>
inline bool operator<=( const Modint<mod> &l, const Modint<mod> &r )
{
    return !( l > r );
}

template <uint_fast64_t mod>
inline bool operator>=( const Modint<mod> &l, const Modint<mod> &r )
{
    return !( l < r );
}

// Modint Equality Womparer

template <uint_fast64_t mod>
inline bool operator==( const Modint<mod> &l, const Modint<mod> &r )
{
    return l.value() == r.value();
}

template <uint_fast64_t mod>
inline bool operator!=( const Modint<mod> &l, const Modint<mod> &r )
{
    return !( l == r );
}
} // namespace mod

using mint_t = mod::Modint<MOD>;

int S[MAX_N];
int T[MAX_M];
mint_t dp[MAX_N + 1][MAX_M + 1];
mint_t sum[MAX_N + 1][MAX_M + 1];

int main( int argc, char **argv )
{
    int N, M;
    cin >> N >> M;

    for ( int i = 0; i < N; i++ ) cin >> S[i];
    for ( int j = 0; j < M; j++ ) cin >> T[j];

    for ( int i = 0; i < N; i++ )
    {
        for ( int j = 0; j < M; j++ )
        {
            if ( S[i] == T[j] ) dp[i + 1][j + 1] = sum[i][j] + 1;
            sum[i + 1][j + 1] =
                sum[i][j + 1] + sum[i + 1][j] - sum[i][j] + dp[i + 1][j + 1];
        }
    }

    cout << ( sum[N][M] + 1 ) << endl;

    // cout << "=== dp ===" << endl;

    // for ( int i = 0; i <= N; i++ )
    //     for ( int j = 0; j <= M; j++ )
    //         cout << "dp[" << i << "][" << j << "] = " << dp[i][j] << endl;

    // cout << "=== sum ===" << endl;

    // for ( int i = 0; i <= N; i++ )
    //     for ( int j = 0; j <= M; j++ )
    //         cout << "sum[" << i << "][" << j << "] = " << sum[i][j] << endl;

    return 0;
}


Measured memory_bytes: 62592