#include<bits/stdc++.h>
/*
#include<atcoder/all>
using namespace atcoder;
//using mint = modint1000000007;
using mint = modint998244353;
*/
//g++ -I/opt/ac-library ./**.cpp
using namespace std;
using ll = long long;
using ull = unsigned long long;
const long long MOD = 1000000007;
const long double PI = 3.14159265358979;
const long long INF = 1LL<<60;
template <typename T> bool chmax(T &a, const T& b){if(a < b){a = b;return true;}return false;}
template <typename T> bool chmin(T &a, const T& b){if(a > b){a = b;return true;}return false;}
#define deb(var) do{cout << #var << " : "; view(var);}while(0)
template<typename T> void view(T e){cout << e << endl;}
void view(vector<string>& v){cout << endl;for(auto& s :v){view(s);}cout << endl;}
template<typename T> void view(vector<T>& v){for(auto& e :v){cout << e << " ";}cout << endl;}
template<typename T> void view(vector<vector<T>>& vv){cout << endl;for(auto& v:vv){view(v);}}
ll gcd(ll a, ll b){if (b == 0) return a;else return gcd(b, a % b);}
ll lcm(ll x,ll y){return ll(x/gcd(x,y))*y;}
template<typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define int long long


int32_t main() {
    int n, k; cin >> n >> k;
    vector<int> a(n);
    string s;
    for (int i=0; i<n; i++) {
        cin >> a[i];
    }
    cin >> s;
    vector<vector<int>> dp(n + 1, vector<int> (k + 1, 0));
    dp[0][0] = 1;
    for (int i=1; i<=n; i++) {
        dp[i][0] = 1;
        for (int j=1; j<=min(k, i); j++) {
            for (int k=1; k<i; k++) {
                if (s[j - 1] == '<') {
                    if (a[k - 1] < a[i - 1]) {
                        dp[i][j] += dp[k][j - 1];
                        dp[i][j] %= MOD;
                    }
                }
                else {
                    if (a[k - 1] > a[i - 1]) {
                        dp[i][j] += dp[k][j - 1];
                        dp[i][j] %= MOD;
                    }
                }
            }
        }
    }
    int ans = 0;
    for (int i=0; i<=n; i++) {
        ans += dp[i][k];
        ans %= MOD;
    }

    cout << ans << "\n";
}