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

int main() {
  int N; cin >> N;
  map<int, int> mp;
  for(int i = 0; i < N; i++){
    int X; cin >> X;
    mp[X]++;
  }
  int i = 0;
  int now = -1;
  int ans = 1000000000;
  for(auto p: mp){
    if(i != 0) ans = min(ans, p.first-now);
    i++;
    now = p.first;
  }
  if(ans == 1000000000) cout << 0 << endl;
  else cout << ans << endl;
}