#include <bits/stdc++.h>
using namespace std;

int64_t solve(string &s, string &t, vector<vector<int>> &edges, vector<int64_t> &dp, int now, int64_t mod)
{
	if (0 <= dp[now])
	{
		return dp[now];
	}
	size_t x = t.find(s[now]) + 1;
	int64_t r = 0;
	for (int next : edges[now])
	{
		if (t.find(s[next]) == x)
		{
			(r += solve(s, t, edges, dp, next, mod)) %= mod;
		}
	}
	return dp[now] = r;
}

int main()
{
	int64_t n, m, mod = 1000000007;
	string s, t = "PDCA";
	cin >> n >> m >> s;
	vector<vector<int>> edges(n);
	for (int i = 0; i < m; i++)
	{
		int p, q;
		cin >> p >> q;
		p--;
		q--;
		edges[p].emplace_back(q);
		edges[q].emplace_back(p);
	}
	vector<int64_t> dp(n, -1);
	for (int i = 0; i < n; i++)
	{
		if (s[i] == 'A')
		{
			dp[i] = 1;
		}
	}
	int64_t ans = 0;
	for (int i = 0; i < n; i++)
	{
		if (s[i] == 'P')
		{
			(ans += solve(s, t, edges, dp, i, mod)) %= mod;
		}
	}
	cout << ans << endl;
	return 0;
}