//叫んで 藻掻もがいて 瞼まぶたを腫らしても
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int , int> pii;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxn = 102;
const ll mod = 1e9+7;
#define pb push_back
#define endl '\n'
#define dokme(x) cout << x , exit(0)
#define ms(x , y) memset(x , y , sizeof x)
ll pw(ll a, ll b, ll md = mod){ll res = 1;while(b){if(b&1){res=(a*res)%md;}a=(a*a)%md;b>>=1;}return(res);}
int n , l , r , k , a[maxn] , prt[maxn];
int ina[maxn] , inb[maxn];
int dp[2510][maxn][maxn];
int Dp(int c , int f , int s){
if(c < 0)return 1e9;
if(dp[c][f][s] != -1)return dp[c][f][s];
if(s == 0)return 0;
if(f == 0)return prt[inb[s]];
if(c == 0)return prt[inb[s]];
dp[c][f][s] = Dp(c , f , s-1) + a[inb[s]];
dp[c][f][s] = min(dp[c][f][s] , Dp(c-1 , f , s));
dp[c][f][s] = min(dp[c][f][s] , Dp(c , f - 1 , s));
dp[c][f][s] = min(dp[c][f][s] , Dp(c - abs(ina[f] - inb[s]) , f - 1 , s - 1) + a[ina[f]]);
return dp[c][f][s];
}
int32_t main(){
ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
cin >> n >> l >> r >> k;
int sz = r - l + 1;
for(int i = 1 ; i <= n ; i ++)
cin >> a[i];
for(int i = l ; i <= r ; i ++)
prt[i] = a[i] + prt[i - 1] , inb[i - l + 1] = i;
for(int i = 1 ; i < l ; i ++)
ina[i] = i;
for(int i = r + 1 ; i <= n ; i ++)
ina[i - r - 1 + l] = i;
ms(dp , -1);
dp[0][0][0] = 0;
cout << Dp(min(k , 2509) , n - sz , sz);
return(0);
}
