// cd /mnt/c/users/murad/onedrive/dokumente
/// https://open.spotify.com/intl-tr/track/13XGeumHl6payK5U9fI0R7?si=c27aa63e897a4bcb
/*
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'*/
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define int long long
#define YES cout << "YES" << '\n';
#define NO cout << "NO" << '\n';
#define Yes cout << "Yes" << '\n';
#define No cout << "No" << '\n';
#define no cout << "no" << '\n';
#define yes cout << "yes" << '\n';
#define fastio \
ios_base::sync_with_stdio(false); \
cin.tie(nullptr);
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define pb push_back
#define pf push_front
#define M_PI 3.14159265358979323846
#define vi vector<long long>
#define pii pair<long long, long long>
#define vii vector<pair<long long, long long>>
#define vvi vector<vector<long long>>
#define FOR0(i, n) for (int i = 0; i < n; ++i)
#define FOR1(i, n) for (int i = 1; i <= n; ++i)
const long long kurdistan = 0;
const long long MOD = 1e9 + 7;
const long long INF = 1e18;
const long long LINF = 4e18;
const long long LOG = 20;
const long long MAXM = 50000;
const long long MAXN = 200000 + 5;
const long long sz = 1e7 + 5;
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T>
void print(const vector<T> &v)
{
for (auto &x : v)
{
cout << x << ' ';
}
cout << '\n';
}
template <typename T>
void input(vector<T> &v)
{
for (auto &x : v)
{
cin >> x;
}
}
int ebob(int a, int b)
{
int g = std::gcd(a, b);
return g;
}
int ekob(int a, int b)
{
int g = std::gcd(a, b);
return (a / g) * b;
}
using namespace __gnu_pbds;
template <typename T>
using indexed_set = tree<
T,
null_type,
less<T>,
rb_tree_tag,
tree_order_statistics_node_update>;
template <typename T>
using indexed_multiset = tree<
pair<T, int>,
null_type,
less<pair<T, int>>,
rb_tree_tag,
tree_order_statistics_node_update>;
///--------------------TEMPLATE END-------------------------------------
int n, p, q;
vi a(2010);
bool f(int w)
{
int i = 0;
int p1 = p;
int q1 = q;
while (i < n)
{
if (p1 + q1 == 0)
{
return false;
}
int best = 0;
bool lr = false;
if (q1 > 0)
{
int lim = a[i] + 2 * w;
int j = i;
while (j < n && a[j] <= lim)
{
j++;
}
if (j - i > best)
{
best = j - i;
lr = true;
}
}
if (p1 > 0)
{
int lim = a[i] + w;
int j = i;
while (j < n && a[j] <= lim)
{
j++;
}
if (j - i > best)
{
best = j - i;
lr = false;
}
}
if (best == 0)
{
return false;
}
if (lr)
{
q1--;
}
else
{
p1--;
}
i += best;
}
return true;
}
void _()
{
cin >> n >> p >> q;
for (int i = 0; i < n; ++i)
{
cin >> a[i];
}
sort(all(a));
int l = 1;
int r = 1e9;
int res = r;
while (l <= r)
{
int mid = (l + r) >> 1;
if (f(mid))
{
res = mid;
r = mid - 1;
}
else
{
l = mid + 1;
}
}
cout << res << '\n';
}
signed main()
{
fastio int t = 1;
// cin >> t;
while (t--)
{
_();
}
}
