///TRAN THAI BAO :3
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
using namespace std;
#define maxN 2007
int n, p, q;
vector<long long>a;
long long dp[maxN][maxN]; //q op req to reach the end after spending j op p and at pos i
int nxtP[maxN];
int nxtQ[maxN];
bool check(long long w)
{
if(p + q >= n)
return true;
int j = 0;
for(int i = 0; i < n; i++)
{
while(j < n && a[j] - a[i] < w)
j++;
nxtP[i] = j;
}
j = 0;
for(int i = 0; i < n; i++)
{
while(j < n && a[j] - a[i] < w*2)
j++;
nxtQ[i] = j;
}
for(int i = 0; i <= p; i++)
dp[n][i] = 0;
for(int i = n-1; i >= 0; i--)
{
for(int j = 0; j <= p; j++)
{
dp[i][j] = dp[nxtQ[i]][j] + 1;
if(j > 0)
dp[i][j] = min(dp[i][j], dp[nxtP[i]][j-1]);
}
}
return dp[0][p] <= q;
}
void solve()
{
cin >> n >> p >> q;
p = min(n, p);
q = min(n, q);
for(int i = 1; i <= n; i++)
{
int x;
cin >> x;
a.push_back(x);
}
sort(a.begin(), a.end());
int lo = 1, hi = 1000000000, mid, ans = 1000000000;
while(lo <= hi)
{
mid = (lo+hi)/2;
if(check(mid))
{
ans = min(ans, mid);
hi = mid-1;
}
else lo = mid+1;
}
cout << ans;
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
solve();
return 0;
}
