#include <bits/stdc++.h>
using namespace std;
int const MAX=2005;
int n,small,big;
int v[MAX];
void read(){
cin>>n>>small>>big;
small=min(small,n);
big=min(big,n);
int i;
for(i=1;i<=n;++i)
cin>>v[i];
sort(v+1,v+n+1);
}
int urmS[MAX],urmB[MAX];
void two_pointers(int w){
int st,dr=1;
for(st=1;st<=n;++st){
while(dr<n && v[dr+1]-v[st]+1<=w)
++dr;
urmS[st]=dr;
}
dr=1;
for(st=1;st<=n;++st){
while(dr<n && v[dr+1]-v[st]+1<=2*w)
++dr;
urmB[st]=dr;
}
}
int dp[MAX][MAX];
void maxself(int& x,int val){
if(x<val)
x=val;
}
bool get_dp(){
int i,j;
bool ok=0;
for(i=0;i<=small && !ok;++i)
for(j=0;j<=big && !ok;++j){
dp[i][j]=0;
if(i)
maxself(dp[i][j],urmS[dp[i-1][j]+1]);
if(j)
maxself(dp[i][j],urmB[dp[i][j-1]+1]);
if(dp[i][j]==n)
ok=1;
}
return ok;
}
bool check(int w){
two_pointers(w);
return get_dp();
}
int bin_search(){
/// (]
int st=0,dr=1e9;
while(dr-st>1){
int mij=(st+dr)/2;
if(check(mij))
dr=mij;
else
st=mij;
}
return dr;
}
int main()
{
read();
cout<<bin_search();
return 0;
}
