#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define sz(x) (int)x.size()
#define ALL(v) v.begin(),v.end()
#define MASK(k) (1LL << (k))
#define BIT(x, i) (((x) >> (i)) & 1)
#define oo (ll)1e18 + 10
#define INF (ll)1e9
#define MOD (ll)(998244353)
using namespace std;
template<class T1, class T2>
bool maximize(T1 &a, T2 b){if(a < b){a = b; return true;} return false;}
template<class T1, class T2>
bool minimize(T1 &a, T2 b){if(a > b){a = b; return true;} return false;}
template<class T1, class T2>
void add(T1 &a, T2 b){a += b; if(a >= MOD) a -= MOD;}
template<class T1, class T2>
void sub(T1 &a, T2 b){a -= b; if(a < 0) a += MOD;}
template<class T>
void cps(T &v){sort(ALL(v)); v.resize(unique(ALL(v)) - v.begin());}
const int MAX = 2e3 + 10;
int N, P, Q;
int a[MAX], dp[MAX][MAX], small[MAX], large[MAX];
void solve(){
cin >> N >> P >> Q;
for(int i = 1; i <= N; i++) cin >> a[i];
sort(a + 1, a + N + 1);
minimize(P, N);
minimize(Q, N);
auto OK = [&](int range) -> bool{
int j = N, k = N;
for(int i = N; i >= 1; i--){
while(a[j] - a[i] + 1 > range) j--;
while(a[k] - a[i] + 1 > 2 * range) k--;
small[i] = j;
large[i] = k;
}
small[N + 1] = large[N + 1] = N;
for(int i = 0; i <= P; i++){
memset(dp[i], 0, (Q + 3) * sizeof(int));
}
for(int i = 0; i <= P; i++) for(int j = 0; j <= Q; j++){
if(i < P){
maximize(dp[i + 1][j], small[dp[i][j] + 1]);
}
if(j < Q){
maximize(dp[i][j + 1], large[dp[i][j] + 1]);
}
}
return dp[P][Q] >= N;
};
int l = 1, r = (int)1e9;
while(l < r){
int m = (l + r) >> 1;
if(OK(m)) r = m;
else l = m + 1;
}
cout << r << "\n";
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
// freopen("task.inp","r",stdin);
// freopen("task.out","w",stdout);
int T = 1;
// cin >> T;
for(; T; T--) solve();
return 0;
}
