// includes
#include <cstdio>
#include <cstdint>
#include <iostream>
#include <iomanip>
#include <string>
#include <queue>
#include <stack>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <algorithm>
#include <utility>
#include <functional>
#include <cmath>
#include <climits>
#include <bitset>
#include <list>
#include <random>

// macros
#define ll long long int
#define pb emplace_back
#define mk make_pair
#define pq priority_queue
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define rep(i, n) FOR(i, 0, n)
#define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--)
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end())

using namespace std;

//  types
typedef pair<int, int> P;
typedef pair<ll, int> Pl;
typedef pair<ll, ll> Pll;
typedef pair<double, double> Pd;
 
// constants
const int inf = 1e9;
const ll linf = 1LL << 50;
const double EPS = 1e-10;
const int mod = 1e9 + 7;

// solve
template <class T>bool chmax(T &a, const T &b){if(a < b){a = b; return 1;} return 0;}
template <class T>bool chmin(T &a, const T &b){if(a > b){a = b; return 1;} return 0;}

int n, m;
string s;
vector<int> edge[100001];
map<char, char> mp;
ll dp[100001];

ll dfs(int i){
  if(dp[i] >= 0)return dp[i];
  if(s[i] == 'A')return 1;
  char next = mp[s[i]];
  ll res = 0;
  for(auto c: edge[i]){
    if(s[c] == next){
      res = (res + dfs(c)) % mod;
    }
  }
  return dp[i] = res;
}

int main(int argc, char const* argv[])
{
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> m;
  cin >> s;
  rep(i, m){
    int u, v;
    cin >> u >> v, u--, v--;
    edge[u].pb(v);
    edge[v].pb(u);
  }
  mp['P'] = 'D';
  mp['D'] = 'C';
  mp['C'] = 'A';
  for(int i = 0; i < n; i++)dp[i] = - 1;
  ll res = 0;
  for(int i = 0; i < n; i++){
    if(s[i] == 'P')res = (res + dfs(i)) % mod;
  }
  cout << res << endl;
	return 0;
}