#pragma GCC optimize ("-O3","unroll-loops")
#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<queue>
#include<map>
#include<math.h>
#include<iomanip>
#include<set>
#include<numeric>
#include<cstring>
#include<cstdio>
#include<functional>
#include<bitset>
#include<limits.h>
#include<cassert>
#include<iterator>
#include<complex>


#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define FORR(i, m, n) for(int i = m;i >= n;i--)
#define SORT(v, n) sort(v, v+n);
#define VSORT(v) sort(v.begin(), v.end());
#define REVERSE(v,n) reverse(v,v+n);
#define VREVERSE(v) reverse(v.begin(), v.end());
#define ll long long
#define pb(a) push_back(a)
#define m0(x) memset(x,0,sizeof(x))
#define print(x) cout<<x<<'\n';
#define pe(x) cout<<x<<" ";
#define lb(v,n) lower_bound(v.begin(), v.end(), n);
#define ub(v,n) upper_bound(v.begin(), v.end(), n);
#define int long long
#define all(x) (x).begin(), (x).end()
#define double long double

using namespace std;

int MOD = (ll)1000000000 + 7;
const ll INF = 1e17;
const double pi = acos(-1);
const double EPS = 1e-10;
typedef pair<int, int>P;
const int MAX = 200020;

vector<int>G[100010];
int PDCA[100010], DCA[100010], CA[100010];
int N, M;
string S;
int ca(int n) {
	if (CA[n] != -1)return CA[n];
	int ret = 0;
	for (auto x : G[n]) {
		if (S[x] == 'A') {
			ret++;
			ret %= MOD;
		}
	}
	CA[n] = ret;
	return ret;
}
int dca(int n) {
	if (DCA[n] != -1)return DCA[n];
	int ret = 0;
	for (auto x : G[n]) {
		if (S[x] == 'C') {
			ret += ca(x);
			ret %= MOD;
		}
	}
	DCA[n] = ret;
	return ret;
}
int pdca(int n) {
	if (PDCA[n] != -1)return PDCA[n];
	int ret = 0;
	for (auto x : G[n]) {
		if (S[x] == 'D') {
			ret += dca(x);
			ret %= MOD;
		}
	}
	PDCA[n] = ret;
	return ret;
}

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

	cin >> N >> M >> S;
	REP(i, M) {
		int u, v; cin >> u >> v;
		u--, v--;
		G[u].pb(v);
		G[v].pb(u);
	}
	int ans = 0;
	REP(i, 100010) {
		PDCA[i] = -1;
		DCA[i] = -1;
		CA[i] = -1;
	}
	REP(i, N) {
		if (S[i] == 'P') {
			ans += pdca(i);
			ans %= MOD;
		}
	}
	print(ans);
}