# include <bits/stdc++.h>
using namespace std;
ifstream fi("koba.in");
ofstream fo("koba.out");
int s[int(1e8 + 5)];
int main(void)
{
    int n,m=0;
    fi >> n >> s[1] >> s[2] >> s[3];
    s[1]%=10;s[2]%=10;s[3]%=10;
    for (m=4;m<=n;++m)
    {
        s[m] = (s[m-1] + s[m-2] * s[m-3]) % 10;
        if (s[m] == s[3] && s[m-1] == s[2] && s[m-2] == s[1]) break;
    }
    if (m < n) m-=3;
    int p = n / m;
    int ans=0;
    for (int i=1;i<=m;++i) ans+=s[i];
    ans*=p;p=n%m;
    for (int i=1;i<=p;++i) ans+=s[i];
    return fo << ans << '\n',0;
}