#include <bits/stdc++.h>
using namespace std;

int main() {
  int N;
  cin >> N;
  vector<int> X(N);
  for (int i = 0; i < N; i++) cin >> X.at(i);
  sort(X.begin(), X.end());

  int ans = 1e9, flag = 0;
  for (int i = 1; i < N; i++) {
    if (X.at(i) - X.at(i - 1)) ans = min(ans, X.at(i) - X.at(i - 1)), flag = 1;
  }

  cout << ((flag) ? ans : 0) << "\n";
}