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

int main(){
	ios::sync_with_stdio(0),cin.tie(0);
	
	ll n,k,m,c,d;
	cin>>n>>k>>m>>c>>d;
	vector<ll> a(n+1);

	for(int i=1;i<=n;i++){
		cin>>a[i];
	}

	auto check=[&](ll x)->bool{
		ll res=0,cnt=0;
		vector<ll> dx(n+1,0);
		for(int i=1;i<=n;i++){
			if(a[i]>=x){
				cnt++;
				continue;
			}
			if(a[i]+c+(m-1)*d<x){
				continue;
			}
			ll temp=0;
			if(a[i]+c>=x){
				temp=0;
			}else{
				temp=(x-a[i]-c)/d+((x-a[i]-c)%d?1:0);
			}
			
			if(i-temp<0){
				continue;
			}
			dx[max(1ll,i-m)]++;
			dx[i-temp]--;
		}
		for(int i=1;i<=n;i++){
			dx[i]+=dx[i-1];
			res=max(res,cnt+dx[i]);
		}
		return res>=k;
	};

	ll l=-1,r=1e18;
	while(l+1!=r){
		ll mid=(l+r)>>1;
		if(check(mid)) l=mid;
		else r=mid;
	}
	cout<<l;
	return 0;
}