#include <bits/stdc++.h>
#define rep(i, ss, ee) for (int i = ss; i < ee; ++i)
using namespace std;

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  int N, x, ans = 1000001;
  cin >> N;
  set<int> s;
  vector<int> v;
  rep(i, 0, N) {
    cin >> x;
    s.emplace(x);
  }
  for (auto x : s) v.emplace_back(x);
  if (v.size() == 1) ans = 0;
  rep(i, 0, v.size() - 1) { ans = min(ans, v[i + 1] - v[i]); }
  cout << ans << endl;
  getchar();
}