#include<bits/stdc++.h>
using namespace std;
using ll = long long ;
ll a[2005], n, small, big, sz_small, sz_big;
bool Can(ll ind, ll s_cnt, ll b_cnt) {
if ( ind == n + 1) return true;
if ( s_cnt == 0 && b_cnt == 0) return false;
if ( s_cnt == 0) return Can(upper_bound(a + 1, a + n + 1, a[ind] + sz_big - 1) - a, s_cnt, b_cnt-1);
if ( b_cnt == 0) return Can(upper_bound(a + 1, a + n + 1, a[ind] + sz_small - 1) - a, s_cnt- 1, b_cnt);
return Can(upper_bound(a + 1, a + n + 1, a[ind] + sz_small - 1) - a, s_cnt- 1, b_cnt) || Can(upper_bound(a + 1, a + n + 1, a[ind] + sz_big - 1) - a, s_cnt, b_cnt-1);
}
bool Solve(ll x) {
sz_small = x;
sz_big = 2 * x;
return Can(1, small , big);
}
int main() {
// freopen("moocast.in", "r", stdin);
// freopen("moocast.out", "w", stdout);
ios::sync_with_stdio(false);
cin.tie(NULL);
ll t, m, ans, s, lo, hi, sum, x, y, r, p, i, j, mid;
cin >> n >> small >> big;
for (i = 1; i <= n; i ++) cin >> a[i];
sort ( a + 1, a + n + 1);
lo = 1;
hi = 1e9;
while ( lo < hi) {
mid =(lo + hi)/2;
if (!Solve(mid)) lo = mid + 1;
else hi = mid;
}
cout << lo << endl;
}
