#include<bits/stdc++.h>
#define REP(i,n) for(int i=0,i##_len=(n);i<i##_len;++i)
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
#define All(x) (x).begin(),(x).end()
using namespace std;
using ll = long long;

int main(){
    int N;cin>>N;
    vector<ll> P(N);
    REP(i,N) cin>>P[i];
    ll ans=1;
    bool zero=false;
    REP(i,N){
        ll q=P[i];
        if(q==0) zero=true;
        ll d=0;
        while(q){
            d+=q%10;
            q/=10;
        }
        d%=9;
        ans*=d;
        ans%=9;
    }
    if(zero) cout<<0<<endl;
    else cout<<(ans?ans:9)<<endl;
}