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

long long n, p, q, ans, tmp;
vector<long long> c, d;

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cin >> n >> p >> q;
	c.resize(n);
	for(auto &i:c) cin >> i;
	d.resize(n);
	for(int i=0; i<n; ++i){
		d[i] = c[i] + p * (i+1);
	}
	sort(d.begin(), d.end());
	ans = tmp = accumulate(c.begin(), c.end(), 0ll);
	for(int i=0; i<n; ++i){
		tmp += p*q + (2*i+1)*p - d[i];
		ans = max(ans, tmp);
	}
	cout << ans << "\n";
}
