#include <bits/stdc++.h>
using namespace std;
const int INF = 1 << 30;
const long long int MAX = 1e9 + 7;
void array_show(int *array, int array_n, char middle = ' ') {
  for (int i = 0; i < array_n; i++)
    printf("%d%c", array[i], (i != array_n - 1 ? middle : '\n'));
}
void array_show(long long int *array, int array_n, char middle = ' ') {
  for (int i = 0; i < array_n; i++)
    printf("%lld%c", array[i], (i != array_n - 1 ? middle : '\n'));
}
void array_show(vector<int> &vec_s, int vec_n = -1, char middle = ' ') {
  if (vec_n == -1) vec_n = vec_s.size();
  for (int i = 0; i < vec_n; i++)
    printf("%d%c", vec_s[i], (i != vec_n - 1 ? middle : '\n'));
}
void array_show(vector<long long int> &vec_s, int vec_n = -1,
                char middle = ' ') {
  if (vec_n == -1) vec_n = vec_s.size();
  for (int i = 0; i < vec_n; i++)
    printf("%lld%c", vec_s[i], (i != vec_n - 1 ? middle : '\n'));
}
namespace sol {
void solve() {
  int n, m;
  int i, j, k;
  int a, b, c;
  cin >> n;
  vector<int> v1;
  for (i = 0; i < n; i++) {
    cin >> a;
    v1.push_back(a);
  }
  sort(v1.begin(), v1.end());
  a = n / 2, b = v1.back();
  for (i = 0; i + a < n; i++) {
    b = min(b, v1[i + a] - v1[i]);
  }
  cout << b << endl;
}
}  // namespace sol
int main() { sol::solve(); }
