#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define lsb(x) (x & (-x))
using namespace std;
const ll INF = 1e15;
const int MAXN = 2005;
int dp[MAXN + 1][MAXN + 1];
ll arr[MAXN + 1];
int nxt_a[MAXN + 1], nxt_b[MAXN + 1];
inline bool check(ll w, int n, int a, int b) {
int i, j;
int pa = 0, pb = 0;
for(i = 0; i <= n; i++) {
while(arr[pa] - arr[i] < w) {
pa++;
}
while(arr[pb] - arr[i] < 2LL * w) {
pb++;
}
nxt_a[i] = pa;
nxt_b[i] = pb;
}
dp[0][0] = 1;
for(int s = 1; s <= a + b; s++) {
for(i = 0; i <= min(a, s); i++) {
j = s - i;
if(j > b) {
continue;
}
dp[i][j] = 0;
if(i > 0) {
dp[i][j] = max(dp[i][j], dp[i - 1][j]);
dp[i][j] = max(dp[i][j], nxt_a[dp[i - 1][j]]);
}
if(j > 0) {
dp[i][j] = max(dp[i][j], dp[i][j - 1]);
dp[i][j] = max(dp[i][j], nxt_b[dp[i][j - 1]]);
}
if(dp[i][j] == n + 1) {
return 1;
}
}
}
return 0;
}
int main() {
//ifstream cin("A.in");
//ofstream cout("A.out");
int i, n, a, b;
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
cin >> n >> a >> b;
for(i = 1; i <= n; i++) {
cin >> arr[i];
}
sort(arr + 1, arr + n + 1);
arr[n + 1] = INF;
a = min(n, a), b = min(b, n);
int res = 0;
for(int step = 1 << 29; step; step >>= 1) {
if(check(res + step, n, a, b) == 0) {
res += step;
}
}
cout << res + 1;
//cin.close();
//cout.close();
return 0;
}
