N,M = map(int,input().split())
S = input()
from collections import defaultdict
dic = defaultdict(list)

for i in range(N):
    dic[S[i]].append(i)
T = "PDCA"

DIV = 1000000007
    
G = [[] for i in range(N)]
for _ in range(M):
    u,v = map(int,input().split())
    if S[u - 1] + S[v - 1] in T:
        G[u - 1].append(v - 1)
    if S[v - 1] + S[u - 1] in T:
        G[v - 1].append(u - 1)

dp = [0] * N
for v in dic["P"]:
    dp[v] = 1
    
for i in range(len(T) - 1):
    for v in dic[T[i]]:
        for child in G[v]:
            dp[child] += dp[v]
            dp[child] %= DIV
    
ans = 0        
for v in dic["A"]:
    ans += dp[v]
    ans %= DIV
    
print(ans)