#include <bits/stdc++.h>
#include <cmath> 
#include <iostream>
#include <cstdlib>
#include <math.h>
#include<stdio.h>
using namespace std;

int main(){
    int n;
    cin >> n;
    int a[n];
    for(int a_i = 0; a_i < n; a_i++){
       cin >> a[a_i];
    }
    int diff1[n],diff2[n];
    for(int a_i = 0; a_i < n; a_i++){
        for(int a_b = 0; a_b < n; a_b++){
        diff1[a_i]=(a[a_i]-a[a_i++]);
            diff2[a_i]=abs(diff1[a_i]);
    }
    }   
    int min=diff2[0];
    for(int i=0;i<n*n;i++){
        if(diff2[i]!=0){
            if(min>diff2[i])
                min=diff2[i];
        }
    }
    cout<<min;
    return 0;
}