#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
const int mxN = (int)2e3+10;
const int LINF = (int)1e9;
int n, p, q;
int a[mxN], P[mxN], Q[mxN], v[mxN], dp[mxN][mxN];
bool work(int w){
for(int i=1,j=1,k=1; i <= n; i++){
while(j<=n and a[j]-a[i]<w)j++;
while(k<=n and a[k]-a[i]<2*w)k++;
P[i]=--j, Q[i]=--k;
}
for(int i = 0; i <= p; i++){
for(int j = 0; j <= q; j++){
dp[i][j]=0;
if(i) dp[i][j] = max(dp[i][j], P[dp[i-1][j]+1]);
if(j) dp[i][j] = max(dp[i][j], Q[dp[i][j-1]+1]);
if(dp[i][j]>=n) return 1;
}
}
return 0;
}
int32_t main() {
ios_base::sync_with_stdio(false); cin.tie(0);
cin >> n >> p >> q;
for(int i = 1; i <= n; i++) cin >> a[i];
sort(a+1,a+n+1);
if(p+q>=n){cout<<1;return 0;}
int l = 1, r = (int)1e9;
while(l<r){
int mid = (l+r)/2;
if(work(mid)) r=mid;
else l=mid+1;
}
cout << l;
}
