from collections import defaultdict

mod = 10**9+7

n, m = map(int,input().split())

S = input()
ind = defaultdict(list)
for i, s in enumerate(S):
    ind[s].append(i)

edge = [[] for _ in range(n)]
for _ in range(m):
    u, v = map(lambda x:int(x)-1,input().split())
    if (S[u] == "P" and S[v] == "D") or (S[u] == "D" and S[v] == "C") or (S[u] == "C" and S[v] == "A"):
        edge[u].append(v)
    elif (S[u] == "D" and S[v] == "P") or (S[u] == "C" and S[v] == "D") or (S[u] == "A" and S[v] == "C"):
        edge[v].append(u)

dp = [0]*n
for p in ind["P"]:
    dp[p] = 1
    for to in edge[p]:
        dp[to] += dp[p]

for d in ind["D"]:
    for to in edge[d]:
        dp[to] += dp[d]
        
for c in ind["C"]:
    for to in edge[c]:
        dp[to] += dp[c]
        
ans = 0
for key in ind["A"]:
    ans += dp[key]
    
print(ans%mod)