#include <bits/stdc++.h>
using namespace std;
int INF = 100000000;
int main(){
  int N;
  cin >> N;
  vector<int> X(N);
  for (int i = 0; i < N; i++){
    cin >> X[i];
  }
  sort(X.begin(), X.end());
  int ans = INF;
  for (int i = 0; i < N - 1; i++){
    if (X[i] != X[i + 1]){
      ans = min(ans, X[i + 1] - X[i]);
    }
  }
  if (ans == INF){
    cout << 0 << endl;
  } else {
    cout << ans << endl;
  }
}