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

const int INF = 1 << 25;

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 res = INF;
  for(int i=1;i<X.size();i++){
    int dif = X[i] - X[i-1];
    if(dif == 0)
      continue;
      
    res = min(res, dif);
  }
  
  if(res == INF)
    res = 0;
    
  cout << res << endl;
  return 0;
}