// UUID: 5a4b713c-5905-44f0-992b-1e1f0cbd5c00
#include <bits/stdc++.h>

using namespace std;
using ll = long long;

const int MAXN = 100'001;
const ll INF = 1e15;
const ll MOD = 1e9+7;

ll a[MAXN], b[MAXN];
vector<pair<ll, ll>> pref[MAXN];
map<ll, ll> value_to_bidx;

void solve() {
    int n, m; cin >> n >> m;
    a[0] = INF;
    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= m; i++) cin >> b[i];
    for (int i = 1; i <= m; i++) {
        value_to_bidx[b[i]] = i;
    }

    vector<ll> st;
    vector<pair<ll, ll>> todo;
    st.emplace_back(0);
    pref[0].emplace_back(0, 1);
    for (int i = 1; i <= m; i++) {
        pref[i].emplace_back(0, 0);
    }
    for (int i = 1; i <= n; i++) {
        
        vector<ll> dp(m+1);
        while (!st.empty() && a[st.back()] <= a[i]) {
            if (todo.back().second == st.back()) todo.pop_back();
            st.pop_back();
        }
        if (value_to_bidx.count(a[i])) todo.emplace_back(st.back()+1, i);
        st.emplace_back(i);
        
        for (auto [l, r] : todo) {
            ll idx = value_to_bidx[a[r]];
            
            auto it1 = upper_bound(pref[idx-1].begin(), pref[idx-1].end(), make_pair(r-1, INF));
            auto it2 = lower_bound(pref[idx-1].begin(), pref[idx-1].end(), make_pair(l-1, 0ll));

            ll val1 = 0;
            ll val2 = 0;
            if (it1 != pref[idx-1].begin()) {
                it1--;
                val1 = it1->second;
            }
            if (it2 != pref[idx-1].begin()) {
                it2--;
                val2 = it2->second;
            }
            ll res = val1 - val2;
            res %= MOD;
            
            if (i == n && idx == m) {
                cout << res << "\n";
                return;
            } else {
                pref[idx].emplace_back(i, pref[idx].back().second + res);
            }
        }
    }

    cout << "0\n";
}

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    int t = 1; 
    // cin >> t;
    while (t--) solve();
    return 0;
}