using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[] NMi => ReadLine().Split().Select(c => int.Parse(c) - 1).ToArray();
    static int[][] NMap(int n) => Enumerable.Repeat(0, n).Select(_ => NMi).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, m) = (c[0], c[1]);
        var s = ReadLine();
        var map = NMap(m);
        var tree = new List<int>[n];
        for (var i = 0; i < n; ++i) tree[i] = new List<int>();
        foreach (var edge in map)
        {
            tree[edge[0]].Add(edge[1]);
            tree[edge[1]].Add(edge[0]);
        }
        var pcount = new int[n];
        for (var i = 0; i < n; ++i)
        {
            if (s[i] == 'D')
            {
                foreach (var next in tree[i]) if (s[next] == 'P') ++pcount[i];
            }
            else if (s[i] == 'C')
            {
                foreach (var next in tree[i]) if (s[next] == 'A') ++pcount[i];
            }
        }
        var ans = 0L;
        var mod = 1_000_000_007;
        for (var i = 0; i < n; ++i)
        {
            if (s[i] == 'D')
            {
                foreach (var next in tree[i]) if (s[next] == 'C') ans += (long)pcount[i] * pcount[next] % mod;
            }
        }
        WriteLine(ans % mod);
    }
}