#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define mod 1000000007

const ll N = (1LL << 31) + 25;
const ll m = (1LL << 32);
vector<bool> bit(N);

void solve()
{
    ll n,i,j,k,x,y,z,target,tot;
    ll q,s1,a,b;
    cin >> q >> s1 >> a >> b;
    ll s = s1;
    ll ans=0;

    while(q-- > 0)
    {

        x = s/2;

        if(s%2 == 1)
        {

            if(!bit[x])
            {
                bit[x] = true;
                ans += x;
            }
        }
        else
        {

            if(bit[x])
            {
                bit[x] = false;
                ans -= x;
            }

        }

        s = (s*a + b)%m;
    }

    cout << ans;

}
int main()
{

    //freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
        ll t=1;
	//cin >> t;

	while(t-- > 0)
	{
	    solve();

	}
}

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define mod 1000000007

const ll N = (1LL << 31) + 25;
const ll m = (1LL << 32);

bitset<N> bit;

void solve()
{

    ll n,i,j,k,x,y,z,target,tot;
    ll q,s1,a,b;
    cin >> q >> s1 >> a >> b;
    ll s = s1;
    ll ans=0;

    while(q-- > 0)
    {

        x = s/2;

        if(s%2 == 1)
        {

            if(bit[x] == 0)
            {
                bit[x] = 1;
                ans += x;
            }
        }
        else
        {

            if(bit[x] == 1)
            {
                bit[x] = 0;
                ans -= x;
            }

        }

        s = (s*a + b)%m;
    }

    cout << ans;
}
int main()
{

    //freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
        ll t=1;
	//cin >> t;

	while(t-- > 0)
	{
	    solve();

	}
}