RT，一直CE，代码不长，求dalao救救孩子吧QAQ

不胜感激！！！

#include<bits/stdc++.h>
using namespace std;

const int N = 1e7 + 10;

int n, a[N];
double ans;

int main () {
	
    int A, B, C;
	scanf("%d%d%d%d%d", &n, &A, &B, &C, &a[1]);

	for(int i = 2; i <= n; i++)
		a[i] = (1ll * a[i - 1] * A + B) % 100000001;
	for(int i = 1; i <= n; i++) a[i] = a[i] % C + 1;
	
    a[n + 1] = a[1];
	for(int i = 1; i <= n; i++)
		ans += 1.0 / max(a[i], a[i + 1]);
    
	printf("%.3lf", ans);
    
	return 0; 
}