#include <bits/stdc++.h>
using namespace std;

const int MOD = int(1e9 + 7);

signed main() {
  ios::sync_with_stdio(false);

  int N, M;
  cin >> N >> M;

  string S;
  cin >> S;

  vector<vector<int>> G(N);
  for (int i = 0; i < M; ++i) {
    int U, V;
    cin >> U >> V;
    G[U - 1].push_back(V - 1);
    G[V - 1].push_back(U - 1);
  }

  vector<int> dp(N);

  for (int i = 0; i < N; ++i) dp[i] += S[i] == 'P';

  for (int i = 0; i < N; ++i) if (S[i] == 'D')
    for (int j : G[i]) if (S[j] == 'P')
      (dp[i] += dp[j]) %= MOD;

  for (int i = 0; i < N; ++i) if (S[i] == 'C')
    for (int j : G[i]) if (S[j] == 'D')
      (dp[i] += dp[j]) %= MOD;

  int ans = 0;
  for (int i = 0; i < N; ++i) if (S[i] == 'A')
    for (int j : G[i]) if (S[j] == 'C')
      (ans += dp[j]) %= MOD;

  cout << ans << endl;

  return 0;
}