#include <stdio.h>

#define FIN "koba.in"
#define FOUT "koba.out"

int N, A, B, C, S[1024];

int solve(int n, int a, int b, int c)
{
    int i, t, sum;

    a %= 10; b %= 10; c %= 10;
    if (n == 1) return a;
    if (n == 2) return a+b;
    if (n == 3) return a+b+c;
    sum = a+b+c; n -= 3;

    for (i = 1; i <= 1000; ++i)
    {
        t = (c+a*b)%10;
        S[i] = S[i-1]+t;
        a = b; b = c; c = t;
    }
    return sum+S[1000]*(n/1000)+S[n%1000];
}

int main(void)
{
    freopen(FIN, "r", stdin);
    freopen(FOUT, "w", stdout);

    scanf("%d %d %d %d", &N, &A, &B, &C);
    printf("%d\n", solve(N, A, B, C));

    return 0;
}