//TLE(?)

#include <bits/stdc++.h>
#include <atcoder/all>
#define rep(i, l, n) for (int i = (l); i < (n); i++)
using namespace std;
using namespace atcoder;
using ll = long long;
template <class T>	using V = vector<T>;
const ll mod = 1000000007;


int main(void) {
	int N, K;	cin >> N >> K;
	V<ll> a(N), b(N);
	rep(i, 0, N) {
		cin >> a[i];
	}
	string s;	cin >> s;

	V<ll> dp(N, 1);
	rep(i, 0, K) {
		V<ll> ndp(N);
		ll t = 1;
		if (s[i] == '>') {
			t = -1;
		}
		rep(j, 0, N) {
			rep(k, 0, j) {
				ndp[j] += ((a[k] - a[j]) * t < 0) * dp[k];
				ndp[j] %= mod;
			}
		}
		rep(j, 0, N) {
			dp[j] = ndp[j];
		}
	}

	ll ans = 0;
	for (ll t : dp) {
		ans += t;
		ans %= mod;
	}
	cout << ans << endl;

	return 0;
}