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

from functools import lru_cache

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[v - 1].append(u - 1)
    if S[v - 1] + S[u - 1] in T:
        G[u - 1].append(v - 1)

@lru_cache(maxsize=1000)
def dfs(x):
    if S[x] == "P":
        return 1
    res = 0
    for child in G[x]:
        res += dfs(child)
        res %= DIV
    return res

ans = 0
for v in dic["A"]:
    ans += dfs(v)
    ans %= DIV
    
print(ans)