#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)

const int MOD = 1e9 + 7;
const string t = "PDCA";
int n, m;
string s;
vector<int> edges[100000];
long long w[100000];

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> m >> s;
  REP (i, m) {
    int u, v;
    cin >> u >> v;
    --u, --v;
    edges[u].push_back(v);
    edges[v].push_back(u);
  }

  queue<int> q;
  REP (i, n) if (s[i] == 'P') {
    q.push(i);
    w[i] = 1;
  }
  long long ret = 0;

  while (!q.empty()) {
    int v = q.front();
    q.pop();
    if (s[v] == 'A') {
      ret += w[v];
      ret %= MOD;
    } else {
      char nxt = t[t.find(s[v]) + 1];
      for (int u: edges[v]) {
        if (s[u] == nxt) {
          if (!w[u])
            q.push(u);
          w[u] += w[v];
        }
      }
    }
  }
    
  cout << ret << endl;
  
  return 0;
}