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


int *a;
int count;


void insert(int x){
    a[count] = x;
    int i=count;
    int parent,tmp;
    //printf("Insert: %d\n",x);
    
    while(i>0){
        //printf("\t%d\n",i);
        parent = (i-1)/2;
        if(a[i]<a[parent]){
            tmp = a[i];
            a[i] = a[parent];
            a[parent] = tmp;
            i=parent;
        }
        else{
            break;
        }
    }
    count++;
}

int extractmin(){
    int ret= a[0];
    
    a[0] = a[count-1];
    count--;
    int i=0;
    int c1, c2, tmp; 
    while(i<count){
        c1 = 2*i +1;
        c2 = 2*i +2;
        //printf("%d %d %d\n",a[i],a[c1],a[c2]);
        if(c1>=count && c2>=count){ //den exei paidia
            break; 
        }
        else if(c2>=count){
            if(a[i]<a[c1]){
                break;
            }
            else if(a[c1]<a[i]){
                tmp = a[i];
                a[i] = a[c1];
                a[c1] = tmp;
                break;
            }
        }
        else if(a[i]<a[c1] && a[i] < a[c2]){
            break;
        }
        else if(a[c1]<=a[c2] && a[c1] <a[i]){
            tmp = a[i];
            a[i] = a[c1];
            a[c1] = tmp;
            i=c1;
        }
        else if(a[c2]<=a[c1] && a[c2] <a[i]){
            tmp = a[i];
            a[i] = a[c2];
            a[c2] = tmp;
            i=c2;
        }       
    }
    return ret;
}

int main(){
    int n; 
    int i;
    int min,tmp;
    int x,y;
    
    scanf("%d",&n);
    a = (int *)malloc(sizeof(int) * n);

    count =0;
    for(int a_i = 0; a_i < n; a_i++){
        scanf("%d",&x);
        insert(x);
    }
    
    x=extractmin();
    y=extractmin();
    min = abs(x-y);
    while(count>0){
        x = extractmin();
        tmp = abs(x-y);
        if(tmp<min){
            min = tmp;
        }
        y = x;
    }
    printf("%d\n",min);
    return 0;
}