#include <cstdio>
#include <iostream>
#include <cstdlib>
#include <ctime>

using namespace std;

long long n, m, k, x;
long long remainder;

long long Power(long long x, long long y, long long k) {
    long long result = 1;
    remainder = x % k;
    while (y > 0) {
        if (y % 2 == 1)
            result = (result * remainder) % k;
        remainder = (remainder * remainder) % k;
        y = y / 2;
    }
    return result;
}

int main(void) {
    //	freopen("circle.in", "r", stdin);
    //	freopen("circle.out", "w", stdout);

    scanf("%lld%lld%lld%lld", &n, &m, &k, &x);

    long long result = Power(10, k, n);
    result = (result * m + x) % n;

    printf("%lld\n", result);

    return 0;
}