#pragma GCC optimize("O3", "inline")
#include <bits/stdc++.h>
using namespace std;
#define ins insert
#define pb push_back
#define int long long int
#define pii pair<int, int>
#define endl '\n'
#define drop(x) cout<<(x)<<endl; return;
#define all(x) x.begin(),x.end()
const int prime = 23,inf = 2e18,mod = 1e9 +7,sze =1e6;
struct node{
int qalanbalaca;
int qalanboyuk;
int maxgedir;
};
int mx[2000][2000];
int vis[2000][2000];
int prec[2000][2];
void mal(){
int n,p,q;
cin>>n>>p>>q;
vector<int> arr(n);
for(int i=0;i<n;i++){
cin>>arr[i];
}
sort(all(arr));
int l = 1;
int r = 1e9;
int ans=r;
int lg =0;
while(l<=r){
lg++;
int mid = (l+r)/2;
int w = mid-1;
int bigw = mid*2 -1;
bool check=false;
int tmx =0;
for(int i=0;i<n;i++){
prec[i][0]=0;
prec[i][1]=0;
prec[i][0] = (--upper_bound(all(arr),arr[i]+w)) - arr.begin();
prec[i][1] = (--upper_bound(all(arr),arr[i]+bigw)) - arr.begin();
}
for(int j=0;j<=min(n,p);j++){
if(check){
break;
}
for(int k=0;k<=min(n,q);k++){
if(check){
break;
}
if(vis[j][k]!=lg){
vis[j][k]=lg;
mx[j][k]=-1;
}
if(j || k){
if(j){
int y = mx[j-1][k];
int i = y+1;
// yeni p kullanicam
if(y>=i-1){
int yer = prec[i][0];
mx[j][k]= max(mx[j][k],yer);
tmx=max(tmx,mx[j][k]);
if(tmx>=n-1){
check=true;
break;
}
}
}
if(k){
int y = mx[j][k-1];
int i = y+1;
if(y>=i-1){
int yer = prec[i][1];
mx[j][k]=max(mx[j][k],yer);
tmx=max(tmx,mx[j][k]);
if(tmx>=n-1){
check=true;
break;
}
}
}
}
}
}
if(tmx>=n-1){
check=true;
}
/*
i ci yere qeder j dene small, k dene big kullanildi
*/
if(check){
// cout<<mid<<" "<<w<<" "<<bigw<<endl;
r=mid-1;
ans=mid;
}
else{
l=mid+1;
}
}
drop(ans);
}
signed main() {
cin.tie(0)->sync_with_stdio(0);
int tt = 1;
// cin>>tt;
while(tt--){
mal();
}
}
