n=int(input())
c=list(map(int,input().split()))
fact=[1]*(n+1)
mod=10**9+7
for i in range(1,n+1):
  fact[i]=fact[i-1]*i%mod
ans=fact[n-1]*(pow(10,n,mod)-1)*pow(9,mod-2,mod)%mod
for i in c:
  ans=ans*pow(fact[i],mod-2,mod)%mod
num=0
for i in range(9):
  num+=(i+1)*c[i]
print(num*ans%mod)