#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

#include <atcoder/modint>
using mint = atcoder::modint1000000007;

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int n, m;
  string s;
  cin >> n >> m >> s;
  vector<pair<int, int>> e(m);
  rep(i, m) {
    int u, v;
    cin >> u >> v;
    --u, --v;
    e[i] = { u, v };
  }
  vector<mint> dp(n, 0);
  rep(i, n) if (s[i] == 'P') dp[i] = 1;
  rep(j, 3) {
    vector<mint> ndp(n, 0);
    for (auto [u, v] : e) {
      rep(_, 2) {
        if (s[u] == "PDCA"[j] && s[v] == "PDCA"[j + 1]) ndp[v] += dp[u];
        swap(u, v);
      }
    }
    swap(dp, ndp);
  }
  mint ans = 0;
  rep(i, n) if (s[i] == 'A') ans += dp[i];
  cout << ans.val() << '\n';
  return 0;
}