#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 5;
int read() {
  int s = 0;
  char c = getchar(), lc = '+';
  while (c < '0' || '9' < c) lc = c, c = getchar();
  while ('0' <= c && c <= '9') s = s * 10 + c - '0', c = getchar();
  return lc == '-' ? -s : s;
}
void write(int x) {
  if (x < 0) putchar('-'), x = -x;
  if (x < 10)
    putchar(x + '0');
  else
    write(x / 10), putchar(x % 10 + '0');
}
void print(int x = -1, char c = '\n') {
  write(x);
  putchar(c);
}
int a[N];
signed main(signed Goodbye, char *Wangang[]) {
  (void)Goodbye, (void)Wangang;
  int n = read(), ans = 1e9 + 7;
  for (int i = 1; i <= n; i++) a[i] = read();
  sort(a + 1, a + 1 + n);
  for (int i = n / 2 + 1; i <= n; i++) ans = min(ans, a[i] - a[i - n / 2]);
  print(ans);
  return 0;
}
