using System.Collections.Generic;
using System;

public class Hello
{
    public static int MOD = 1000000007;
    static void Main()
    {
        string[] line = Console.ReadLine().Trim().Split(' ');
        var n = int.Parse(line[0]);
        var m = int.Parse(line[1]);
        var s = Console.ReadLine().Trim();
        var aa = new List<int>[n];
        for (int i = 0; i < n; i++) aa[i] = new List<int>();
        for (int i = 0; i < m; i++)
        {
            line = Console.ReadLine().Trim().Split(' ');
            var a = int.Parse(line[0]) - 1;
            var b = int.Parse(line[1]) - 1;
            if (s[a] == 'P' && s[b] == 'D') aa[b].Add(a);
            else if (s[a] == 'D' && s[b] == 'P') aa[a].Add(b);
            else if (s[a] == 'D' && s[b] == 'C') aa[b].Add(a);
            else if (s[a] == 'C' && s[b] == 'D') aa[a].Add(b);
            else if (s[a] == 'C' && s[b] == 'A') aa[b].Add(a);
            else if (s[a] == 'A' && s[b] == 'C') aa[a].Add(b);
        }
        var bb = new List<int>[4];
        for (int i = 0; i < 4; i++) bb[i] = new List<int>();
        var d = new Dictionary<char, int>();
        var s0 = "PDCA";
        for (int i = 0; i < 4; i++) d[s0[i]] = i;
        for (int i = 0; i < n; i++) bb[d[s[i]]].Add(i);
        getAns(n, aa, bb);
    }
    static void getAns(int n, List<int>[] aa, List<int>[] bb)
    {
        var dp = new long[n];
        foreach (var x in bb[0]) dp[x] = 1;
        for (int i = 1; i < 4; i++)
        {
            foreach (var x in bb[i])
                foreach (var y in aa[x])
                {
                    dp[x] += dp[y];
                    dp[x] %= MOD;
                }
        }
        var ans = 0L;
        foreach (var x in bb[3])
        {
            ans += dp[x];
            ans %= MOD;
        }
        Console.WriteLine(ans);
    }
}