// #include <bits/stdc++.h>
#include <iostream>
#include <cmath>
#include <algorithm>
#include <map>
#include <unordered_map>
#include <vector>
#include <iomanip>
#include <string>
#include <queue>
#include <set>
#include <deque>
using namespace std;
#define int long long
#define endl "\n"
#define fi first
#define se second
const int M=1203465797;
const int inf = 1e14;
const int LOG=18;
const int N=2e3+5;
int n , m , c , w , k , t=1 , q=1 , x , y , z , l , r;
int dp[N][N];
void solve(){
int p,q;
cin >> n >> p >> q;
vector<int>a(n+2);
for (int i=1;i<=n;i++){
cin >> a[i];
}
if (p+q>=n){
cout << 1 << endl;
return;
}
sort(a.begin(),a.end());
int l=0;
int h=((int)1e9+p+q-1)/(p+q);
int m=(l+h)/2;
while (l<h){
for (int i=0;i<=p;i++){
for (int j=0;j<=q;j++){
dp[i][j]=0;
}
}
vector<int>rcp(n+2);
vector<int>rcq(n+2);
rcp[n+1]=rcq[n+1]=n;
for (int i=1;i<=n;i++){
for (int j=i;j<=n;j++){
if (a[j]-a[i]<m){
rcp[i]=j;
}
if (a[j]-a[i]<2*m){
rcq[i]=j;
}
}
}
for (int i=0;i<=p;i++){
for (int j=0;j<=q;j++){
if (i){
dp[i][j]=max(dp[i][j],rcp[dp[i-1][j]+1]);
}
if (j){
dp[i][j]=max(dp[i][j],rcq[dp[i][j-1]+1]);
}
}
}
if (dp[p][q]==n){
h=m;
}
else{
l=m+1;
}
m=(l+h)/2;
}
cout << m << endl;
}
signed main()
{
ios::sync_with_stdio(0);//DO NOT USE IN INTERACTIVE
cin.tie(0), cout.tie(0);//DO NOT USE IN INTERACTIVE
cout << fixed << setprecision(9);
srand(time(0));
// int t=1;
// cin >> t;
for (int _=1;_<=t;_++){
solve();
q++;
}
}
