#include <map>

#include <ctime>

#include <cmath>

#include <queue>

#include <cstdio>

#include <cstring>

#include <iostream>

#include <algorithm>

using namespace std;

#define F(i,j,k) for (int i=j;i<=k;++i)

#define D(i,j,k) for (int i=j;i>=k;--i)

int a[10000005],n,A,B,C;

double ans;

int main()

{

    scanf("%d%d%d%d%d",&n,&A,&B,&C,a+1);

    for (int i=2;i<=n;i++) a[i] = ((long long)a[i-1] * A + B) % 100000001;

    for (int i=1;i<=n;i++) a[i] = a[i] % C + 1;

    F(i,1,n-1) ans+=1.0/max(a[i],a[i+1]);

    ans+=1.0/max(a[n],a[1]);

    printf("%.3f\n",ans);

}