import std.stdio, std.array, std.string, std.conv, std.algorithm;
import std.typecons, std.range, std.random, std.math, std.container;
import std.numeric, std.bigint, core.bitop, core.stdc.string;

immutable long MOD = 10^^9 + 7;

void main() {
    auto s = readln.split.map!(to!int);
    auto N = s[0];
    auto M = s[1];
    auto S = readln.chomp;
    auto G = new int[][](N);
    foreach (_; 0..M) {
        s = readln.split.map!(to!int);
        G[s[0]-1] ~= s[1]-1;
        G[s[1]-1] ~= s[0]-1;
    }

    auto cnt = new long[](N);

    foreach (i; N.iota.filter!(i => S[i] == 'D'))
        foreach (j; G[i].filter!(j => S[j] == 'P'))
            ++cnt[i];

    long ans = 0;

    foreach (i; N.iota.filter!(i => S[i] == 'C')) {
        long p = 0;
        long a = 0;
        foreach (j; G[i].filter!(j => S[j] == 'D'))
            p += cnt[j];
        foreach (j; G[i].filter!(j => S[j] == 'A'))
            a += 1;
        ans += p * a % MOD;
        ans %= MOD;
    }

    ans.writeln;
}