#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;
#define INF 100000000

int main(){
  int N;
  cin >> N;
  vector<int> X;
  rep(i,N){
    int x;
    cin >> x;
    X.push_back(x);
  }
  sort(ALLOF(X));

  int ret = INF;
  rep(i,N-1){
    if(X[i]==X[i+1]) continue;
    ret = min(ret, X[i+1]-X[i]);
  }
  if(ret == INF) ret = 0;

  cout << ret << endl;
    
  return 0;
}