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

#define int long long
#define rep(i,l,r) for(int i=(int)(l);i<(int)(r);i++)
#define all(x) (x).begin(),(x).end()
#define pb push_back
template<class T>bool chmax(T &a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T &a,T b){if(a>b){a=b;return 1;}return 0;}

typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;

const int inf = 1LL<<60;
const int mod = 1e9 + 7;
const double eps = 1e-9;

/*{
}*/

signed main()
{
  int n, m;
  string s;
  cin >> n >> m >> s;

  vector<pii> pd, dc, ca;
  vi dp(n);
  rep(i, 0, m){
    int a, b;
    cin >> a >> b;
    a--; b--;

    if(s[a] < s[b]) swap(a, b);

    if(s[a] == 'P' and s[b] == 'D'){
      pd.pb({a, b});
      dp[a] = 1;
    }else if(s[a] == 'D' and s[b] == 'C'){
      dc.pb({a, b});
    }else if(s[a] == 'C' and s[b] == 'A'){
      ca.pb({a, b});
    }
  }

  for(auto e : pd){
    (dp[e.second] += dp[e.first]) %= mod;
  }

  for(auto e : dc){
    (dp[e.second] += dp[e.first]) %= mod;
  }

  int ans = 0;
  for(auto e : ca){
    (ans += dp[e.first]) %= mod;
  }

  cout << ans << endl;

  return 0;
}