// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
// #pragma GCC optimize("unroll-loops")
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/trie_policy.hpp>
// #include <ext/rope>
// using namespace __gnu_pbds;
// using namespace __gnu_cxx;
#include "bits/stdc++.h"
using namespace std;
#define li long long
#define ld long double
#define ii pair<int, int>
#define vi vector<int>
#define vvi vector<vi>
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pf push_front
#define eb emplace_back
#define em emplace
#define ob pop_back
#define om pop
#define of pop_front
#define fori(i, a, b) for(int i = (int) (a); i <= (int) (b); ++i)
#define ford(i, a, b) for(int i = (int) (a); i >= (int) (b); --i)
#define forIT(it, begin, end) for(__typeof(end) it = (begin) + ((begin) > (end)); it != (end) - ((begin) > (end)); it += 1 - 2 * ((begin) > (end)))
#define b_e(x) begin(x), end(x)
#define sz(x) ((int)(x).size())
#define bitc __builtin_popcountll
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define rand rng
#define endl '\n'
#define sp ' '
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
void solve();
signed main() {
// freopen("test.inp","r",stdin);
// freopen("test.out","w",stdout);
fastio;
int tc = 1;
fori(test, 1, tc) {
solve();
}
return 0;
}
#define int long long
const ld pi = 4 * atan(1.0), eps = 1e-9;
const int maxn = 2005;
int n, p, q;
int arr[maxn];
int to[maxn];
int t2[maxn];
int dp[maxn][maxn];
bool ok(int w) {
int pt = n;
ford(i, n, 1) {
while(arr[pt] - arr[i] >= w) --pt;
to[i] = pt;
}
pt = n;
ford(i, n, 1) {
while(arr[pt] - arr[i] >= 2 * w) --pt;
t2[i] = pt;
}
fori(i, 0, n) fori(j, 0, n) dp[i][j] = 0;
fori(i, 0, p) fori(j, 0, q) {
int idx = dp[i][j];
if(idx == n) return 1;
dp[i + 1][j] = max(dp[i + 1][j], to[dp[i][j] + 1]);
dp[i][j + 1] = max(dp[i][j + 1], t2[dp[i][j] + 1]);
}
return 0;
}
void solve() {
cin >> n >> p >> q; p = min(p, n); q = min(q, n);
fori(i, 1, n) cin >> arr[i];
sort(arr + 1, arr + n + 1);
int lo = 1, hi = 1e9;
while(lo < hi) {
int mi = lo + hi >> 1;
if(ok(mi)) hi = mi;
else lo = mi + 1;
}
cout << lo;
}
