#include <bits/stdc++.h>
using namespace std;
const int maxn = 505;
int n, p, q;
int a[maxn];
int findPos(int pos, int delta)
{
int l = 1;
int r = pos;
while (l <= r)
{
int mid = (l + r) / 2;
if (a[pos] - a[mid] <= delta)
{
r = mid - 1;
}
else
{
l = mid + 1;
}
}
return l;
}
bool dp[maxn][maxn][maxn];
int prvSmall[maxn];
int prvBig[maxn];
bool check(int w)
{
for (int i = 1; i <= n; ++i)
{
prvSmall[i] = findPos(i, w - 1);
prvBig[i] = findPos(i, 2 * w - 1);
}
for (int i = 0; i <= p; ++i)
{
for (int j = 0; j <= q; ++j)
{
dp[0][i][j] = true;
if (i + j >= 1)
{
dp[1][i][j] = true;
}
}
}
for (int pos = 2; pos <= n; ++pos)
{
for (int currp = 0; currp <= p; ++currp)
{
for (int currq = 0; currq <= q; ++currq)
{
dp[pos][currp][currq] = false;
if (currp >= 1)
{
dp[pos][currp][currq] |= dp[pos][currp - 1][currq];
dp[pos][currp][currq] |= dp[prvSmall[pos] - 1][currp - 1][currq];
}
if (currq >= 1)
{
dp[pos][currp][currq] |= dp[pos][currp][currq - 1];
dp[pos][currp][currq] |= dp[prvBig[pos] - 1][currp][currq - 1];
}
}
}
}
return dp[n][p][q];
}
void fastIO()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
int main()
{
fastIO();
cin >> n >> p >> q;
for (int i = 1; i <= n; ++i)
{
cin >> a[i];
}
sort(a + 1, a + n + 1);
p = min(p, n);
q = min(q, n);
p = min(p, n - q);
if (q == n || p == n)
{
cout << 1 << endl;
return 0;
}
int l = 1;
int r = (a[n] - a[1]) / (p + 2 * q);
while (l <= r)
{
int mid = (l + r) / 2;
if (check(mid) == true)
{
r = mid - 1;
}
else
{
l = mid + 1;
}
}
cout << l << endl;
return 0;
}
