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

#define rep(i,j,n) for(int i=j;i<n;++i)
#define all(i) i.begin(),i.end()
#define rall(i) i.rbegin(), i.rend()
#define INF 1e9
#define LINF 1e18
const int mod = 1e9 + 7;

typedef long long i64;
typedef pair<int, int> pi;

template <class T> using vt = vector<T>;
template <class T> using vvt = vector<vector<T>>;

i64 gcd(i64 n, i64 m) {return (m == 0? n : gcd(m, n % m));}
i64 lcd(i64 n, i64 m) {return (n / gcd(n, m) * m);}
int dx[] = {1, 0, -1, 0};
int dy[] = {0, 1, 0, -1};

int n, m;
string s;
vvt<int> edge;
vt<int> dp;

int dfs(int v) {
  if(dp[v] != -1) return dp[v];
  if(s[v] == 'A') return dp[v] = 1;

  int res = 0;
  for(auto &e : edge[v]) {
    if(s[v] == 'P' && s[e] == 'D') res += dfs(e);
    if(s[v] == 'D' && s[e] == 'C') res += dfs(e);
    if(s[v] == 'C' && s[e] == 'A') res += dfs(e);
    res %= mod;
  }
  return dp[v] = res;
}

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

  cin >> n >> m >> s;
  edge = vvt<int>(n);
  rep(i, 0, m) {
    int u, v;
    cin >> u >> v;
    --u; --v;
    edge[u].push_back(v);
    edge[v].push_back(u);
  }

  dp = vt<int>(n, -1);
  int ans = 0;
  rep(i, 0, n) {
    if(s[i] == 'P') ans += dfs(i);
    ans %= mod;
  }
  cout << ans << endl;
}