MOD = 10**9+7

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

dp=[[1]*(M+1) for i in range(N+1)]
S_index=[set() for i in range(10**5+1)]

for i in range(N):
  S_index[S[i]].add(i)
  for j in range(M):
    dp[i][j]=dp[i][j-1]
    for k in S_index[T[j]]:
      dp[i][j]=(dp[i][j]+dp[k-1][j-1])%MOD
      
print(dp[N-1][M-1])
