#include <bits/stdc++.h>
#include <atcoder/string>
#include <atcoder/modint>
using namespace std;
using Modint = atcoder::modint1000000007;

int main(){
    int N;
    cin >> N;
    vector<pair<char, int>> A(N);
    for(auto& [c, a] : A) cin >> a;
    for(auto& [c, a] : A) cin >> c;
    auto Z = atcoder::z_algorithm(vector(A.begin() + 1, A.end()));
    Z.push_back(0);
    vector<Modint> sum(N);
    sum[0] = Modint::raw(A[0].second);
    for(int i = 1; i < N; i++) sum[i] = sum[i - 1] + Modint::raw(A[i].second);
    const auto [c0, a0] = A[0];
    Modint ans = 0;
    for(int i = 0; i < N; i++) if(auto [c, a] = A[i]; c == c0){
        if(a < a0){
            ans += uint64_t(a) * (a + 1) / 2;
            continue;
        }
        ans += uint64_t(a0) * (a + a - a0 - 1) / 2;
        const int z = Z[i];
        ans += sum[z];
        if(i + 1 + z < N && A[i + 1 + z].first == A[1 + z].first){
            ans += Modint::raw(min(A[i + 1 + z].second, A[1 + z].second));
        }
    }
    cout << ans.val() << endl;
}