#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, p, q;
cin >> n >> p >> q;
vector<int> a(n + 1);
for (int i = 1; i <= n; i++) {
cin >> a[i];
}
ranges::sort(a);
p = min(p, n);
q = min(q, n);
auto good = [&](int k) {
vector<vector<int>> dp(p + 1, vector<int>(q + 1));
dp[0][0] = 0;
for (int i = 0; i <= p; i++) {
for (int j = 0; j <= q; j++) {
int s = dp[i][j] + 1;
if (s >= n + 1) {
return true;
}
if (i < p) {
int pos = s;
while (pos <= n && a[pos] - a[s] < k) {
pos++;
}
dp[i + 1][j] = max(dp[i + 1][j], pos - 1);
}
if (j < q) {
int pos = s;
while (pos <= n && a[pos] - a[s] < 2 * k) {
pos++;
}
dp[i][j + 1] = max(dp[i][j + 1], pos - 1);
}
}
}
return false;
};
int l = 0, r = 1e9 + 1;
while (l + 1 < r) {
int m = (l + r) / 2;
if (good(m)) {
r = m;
} else {
l = m;
}
}
cout << r << '\n';
return 0;
}
