#include <iostream>
#include <vector>
using namespace std;
const long long MOD = 1000000007;
int main(){
	int N, M;
	cin >> N >> M;
	string S;
	cin >> S;
	vector<vector<int>> E(N);
	for (int i = 0; i < M; i++){
		int u, v;
		cin >> u >> v;
		u--;
		v--;
		E[u].push_back(v);
		E[v].push_back(u);
	}
	string T = "PDCA";
	vector<vector<long long>> dp(4, vector<long long>(N, 0));
	for (int i = 0; i < N; i++){
		if (S[i] == T[0]){
			dp[0][i] = 1;
		}
	}
	for (int i = 0; i < 3; i++){
		for (int j = 0; j < N; j++){
			if (S[j] == T[i]){
				for (int k : E[j]){
					if (S[k] == T[i + 1]){
						dp[i + 1][k] += dp[i][j];
						dp[i + 1][k] %= MOD;
					}
				}
			}
		}
	}
	long long ans = 0;
	for (int i = 0; i < N; i++){
		ans += dp[3][i];
	}
	cout << ans << endl;
}