#include <bits/stdc++.h>
#pragma optimize "DostSeferoğlu"
#pragma GCC optimize("unroll-loops,Ofast")
#pragma GCC target("avx2,tune=native")
using namespace std;
#define int long long
#define pii pair<int,int>
#define bg begin
#define vi vector<int>
#define endl '\n'
#define vvi vector<vi>
#define vp vector<pii>
#define sp << " " <<
#define all(x) x.bg()+1,x.end()
#define ff first
#define ss second
#define brake {cout << "OK\n";return;}
#define debug(x) {cout << #x << ": "; for (auto it : x) cout << it << " ";cout << endl;}
#define FF(xxx,sss,yyy) for (int xxx=sss;xxx<=yyy;++xxx)
#define F(xx,yy) for (int xx=1;xx<=yy;++xx)
#define pb push_back
const int inf = 1e18;
const int MOD = 998244353;
const int N = 2e5+1;
//4397524
void solve() {
int n,l,r,K;
cin >> n >> l >> r >> K;
int rng = (r-l+1);
vvi dp(rng+1,vi(K+1,inf)),dp2(rng+1,vi(K+1,inf));
dp2[0][0] = 0;
vi a(n+1);
F(i,n) cin >> a[i];
F(i,n) {
FF(j,0,rng) {
FF(k,0,K) {
dp[j][k] = min(dp[j][k],dp2[j][k]);
if (k >= abs(l+j-1-i) && j) {
dp[j][k] = min(dp[j][k],dp2[j-1][k-abs(l+j-1-i)]+a[i]);
}
}
}
dp2 = dp;
}
int mini = inf;
FF(k,0,K) mini = min(mini,dp[rng][k]);
cout << mini << endl;
}
signed main() {
ios_base::sync_with_stdio(0);cin.tie(0);
/* #ifdef Local
freopen("input.in", "r", stdin);
freopen("input.out", "w", stdout);
#endif */
int t = 1;
//cin >> t;
while (t --> 0) solve();
}
