#include <bits/stdc++.h>
#define int long long
#define double long double
using namespace std;
const int MOD = 1000000007;
const int INF = 1e14;
using Graph = vector<vector<int>>;

signed main(){
  int N;
  cin >> N;
  vector<int> A(N);
  for( int i = 0; i < N; i++ ) cin >> A[i];
  sort(A.begin(), A.end());
  int ans = -1;
  for( int i = 1; i < N; i++ ){
    if( abs(A[i]-A[i-1]) != 0 && (ans== -1 || ans > abs(A[i]-A[i-1])) ) ans = abs(A[i]-A[i-1]);
  }
  if( ans != -1 ) cout << ans << endl;
  else cout << 0 << endl;
}