#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt(x) __builtin_popcount(x)
#define pb push_back
#define popf pop_front
#define popb pop_back
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {print(v[i]); cerr << " "; } cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
int ka() {
int x = 0;
bool z = false;
while (1)
{
char y = getchar();
if (y == '-')
z = true;
else if ('0' <= y && y <= '9')
x = x * 10 + y - '0';
else
{
if (z)
x *= -1;
return x;
}
}
}
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
fastIO();
if (str != "") {
freopen((str + ".in").c_str(), "r", stdin);
freopen((str + ".out").c_str(), "w", stdout);
}
}
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int N = 101, M = (1e4 + 1) / 4, inf = 1e9;
int dpL[N][N][M];
int dpR[N][N][M];
int n, l, r, k;
int a[N];
int solveL(int li, int ri, int cur) {
if(li == 0 || ri == l - 1) {
return 0;
}
if(dpL[li][ri][cur] != inf) {
return dpL[li][ri][cur];
}
int ans = min(solveL(li - 1, ri, cur), solveL(li, ri - 1, cur));
if(cur - (ri - li) >= 0) {
ans = min(ans, solveL(li - 1, ri - 1, cur - (ri - li)) + a[li] - a[ri]);
}
dpL[li][ri][cur] = ans;
return ans;
}
int solveR(int li, int ri, int cur) {
if(li == r + 1 || ri == n + 1) {
return 0;
}
if(dpR[li][ri][cur] != inf) {
return dpR[li][ri][cur];
}
int ans = min(solveR(li + 1, ri, cur), solveR(li, ri + 1, cur));
if(cur >= (ri - li)) {
ans = min(ans, solveR(li + 1, ri + 1, cur - (ri - li)) + a[ri] - a[li]);
}
dpR[li][ri][cur] = ans;
return ans;
}
void solve_() {
cin >> n >> l >> r >> k;
k = min(k, M);
for(int i = 1; i <= n; i++) {
cin >> a[i];
}
int s = 0;
for(int i = l; i <= r; i++) {
s += a[i];
}
;
for(int i = 0; i < N; i++) {
for(int j = 0; j < N; j++) {
for(int e = 0; e < M; e++) {
dpL[i][j][e] = inf;
dpR[i][j][e] = inf;
}
}
}
int ans = s, mn = inf;
for(int i = 0; i <= k; i++) {
mn = min(mn, solveL(l - 1, r, i));
mn = min(mn, solveR(l, r + 1, i));
}
for(int i = l; i < r; i++) {
for(int j = 0; j <= k; j++) {
mn = min(mn, solveL(l - 1, i, j) + solveR(i + 1, r + 1, k - j));
}
}
cout << ans + mn << '\n';
}
int main() {
setIO();
auto solve = [&](int test_case)-> void {
while(test_case--) {
solve_();
}
};
int test_cases = 1;
// cin >> test_cases;
solve(test_cases);
return 0;
}
