#include<iostream>
#include<vector>
#include<queue>
#include<stack>
#include<algorithm>
#include<limits.h>
#include<math.h>
#include<map>
#include<set>
#include<unordered_map>
#include<unordered_set>
#include<iomanip>
#include<cstring>
#include<random>
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using namespace std;
int n,p,q;
int arr[2000];
int nxt1[2001];
int nxt2[2001];
bool get(int w){
nxt1[n]=n;
nxt2[n]=n;
for(int i=0;i<n;i++){
nxt1[i]=i;
while(nxt1[i]<n&&arr[nxt1[i]]<arr[i]+w)
nxt1[i]++;
}
for(int i=0;i<n;i++){
nxt2[i]=i;
while(nxt2[i]<n&&arr[nxt2[i]]<arr[i]+2*w)
nxt2[i]++;
}
vector<vector<int>>dp(p+1,vector<int>(q+1)); // dp[i1][i2] = how far can you come with using i1 small and i2 big cameras
for(int i1=0;i1<=p;i1++){
for(int i2=0;i2<=q;i2++){
if(i1){
dp[i1][i2]=max(dp[i1][i2],nxt1[dp[i1-1][i2]]);
}
if(i2){
dp[i1][i2]=max(dp[i1][i2],nxt2[dp[i1][i2-1]]);
}
}
}
return dp[p][q]==n;
}
void solve(){
cin>>n>>p>>q;
p=min(n,p);
q=min(n,q);
for(int i=0;i<n;i++)
cin>>arr[i];
sort(arr,arr+n);
int l=0,r=1e9;
while(l<r-1){
int m=(l+r)/2;
if(get(m))
r=m;
else
l=m;
}
cout<<r<<"\n";
}
int main(){
ios::sync_with_stdio(false);cout.tie(NULL);cin.tie(NULL);
//freopen("/Users/jakob/cp_testing/test.txt","r",stdin);freopen("output.out","w",stdout);
int t=1;//cin>>t;
while(t--)solve();
return 0;
}
/*
3 1 1
2
11
17
*/
