#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int n,k; 
    scanf("%d",&n);
    int *a = malloc(sizeof(int) * n);
    for(int a_i = 0; a_i < n; a_i++){
       scanf("%d",&a[a_i]);
    }
    k=n*(n-1)/2;
    int i,j, diff[k],p=0;
    for(i=0;i<n;i++){
        for(j=0;j<n;j++){
            if(j!=i){
                if(a[i]>a[j])
                    diff[p]=a[i]-a[j];
                else
                    diff[p]=a[j]-a[i];
                p++;
            }
        }
    }
    int min=diff[0];
    for(i=0;i<k;i++){
        if(diff[i]<diff[0])
            min=diff[i];
    }
    printf("%d",min);
    // your code goes here
    return 0;
}