#include <iostream>
#include <algorithm>
#include <cstdio>
#include <string>

#define ll long long

using namespace std;


int main(){
    
    string N;
    cin>>N;
    
    int sum=0,last=-1,flag=-1;
    for(int i=0;i<N.length();++i){
        sum+=N[i]-'0';
        if(i==N.length()-1) last=N[i]-'0';
    }
    flag=(sum%3)+3*((sum%3+last)%2);
    
    int answer=-1;
    switch(flag){
        case 1: answer=2; break;
        case 2: answer=8; break;
        case 3: answer=5; break;
        case 4: answer=7; break;
        case 5: answer=1; break;
        case 0: answer=4; break;
    }

    cout<<answer<<endl;

    return 0;
}