N,M=map(int,input().split())
S=input().strip()

E=[[] for i in range(N)]

for i in range(M):
    x,y=map(int,input().split())
    x-=1
    y-=1
    E[x].append(y)
    E[y].append(x)

mod=10**9+7

DP=[0]*N

for i in range(N):
    if S[i]=="P":
        DP[i]=1

DP2=[0]*N

for i in range(N):
    if DP[i]>0:
        for to in E[i]:
            if S[to]=="D":
                DP2[to]+=DP[i]

DP3=[0]*N

for i in range(N):
    if DP2[i]>0:
        for to in E[i]:
            if S[to]=="C":
                DP3[to]+=DP2[i]

DP4=[0]*N

for i in range(N):
    if DP3[i]>0:
        for to in E[i]:
            if S[to]=="A":
                DP4[to]+=DP3[i]

ANS=sum(DP4)

print(ANS%mod)