#include <bits/stdc++.h>

using namespace std;

#ifdef DEBUG_MODE
	#define DBG(n) n;
#else
	#define DBG(n) ;
#endif
#define REP(i,n) for(ll (i) = (0);(i) < (n);++i)
#define PB push_back
#define MP make_pair
#define FI first
#define SE second
#define SHOW1d(v,n) {for(int W = 0;W < (n);W++)cerr << v[W] << ' ';cerr << endl << endl;}
#define SHOW2d(v,i,j) {for(int aaa = 0;aaa < i;aaa++){for(int bbb = 0;bbb < j;bbb++)cerr << v[aaa][bbb] << ' ';cerr << endl;}cerr << endl;}
#define ALL(v) v.begin(),v.end()
#define Decimal fixed<<setprecision(20)
#define INF 1000000000
#define LLINF 1000000000000000000
#define MOD 1000000007

typedef long long ll;
typedef pair<ll,ll> P;

int main(){
	
	ll n,q,p;cin >> n >> p >> q;
	vector<ll> v;
	ll sum = 0;
	REP(i,n){
		ll c;cin >> c;
		sum += c;
		v.PB(- c + (q - i) * p);
	}
	
	sort(ALL(v),greater<ll>());
	
	ll ans = sum;
		
	REP(i,n){
		sum += v[i];
		ans = max(ans,sum + i * (i + 1) * p);
	}
	
	cout << ans << endl;
	
	return 0;
}
