from collections import defaultdict
MOD = 998244353
N,M = list(map(int,input().split()))
S = input()

all_hatena = S.count("?")
edge = defaultdict(list)
for _ in range(M):
    a,b = list(map(int,input().split()))
    a -= 1;b -= 1
    edge[a].append(b)
    edge[b].append(a)

hatena_count = 0
def f(n,depth):
    global hatena_count
    if(depth == 3):return 26**(all_hatena - hatena_count)
    ret = 0
    for i in edge[n]:
        if(i in visited):continue
        if("aoi"[depth] != S[i] and S[i] != "?"):continue
        if(S[i] == "?"):hatena_count += 1
        visited.add(i)
        ret += f(i,depth+1)
        visited.remove(i)
        if(S[i] == "?"):hatena_count -= 1
    return ret

ans = 0
for i in range(N):
    if(S[i] == "a" or S[i] == "?"):
        hatena_count = 0 if S[i] != "?" else 1
        visited = set()
        visited.add(i)
        ans += f(i,1)
print(ans)