#include<stdio.h>
void quicksort(long int *,int,int);
int main()
{
	int n;
	scanf("%d",&n);
	long int a[n];
	for(int i=0;i<n;i++)
	scanf("%ld",&a[i]);
	quicksort(a,0,n-1);
	int diff=a[n-1]-a[n-2];
	for(int i=n-2;i>1;i--)
	{
		int sub=a[i]-a[i-1];
		if(diff>sub)
		diff=sub;
	}
	printf("%d",diff);
	return 0;
}
void quicksort(long int x[],int first,int last){
    int pivot,j,temp,i;

     if(first<last){
         pivot=first;
         i=first;
         j=last;

         while(i<j){
             while(x[i]<=x[pivot]&&i<last)
                 i++;
             while(x[j]>x[pivot])
                 j--;
             if(i<j){
                 temp=x[i];
                  x[i]=x[j];
                  x[j]=temp;
             }
         }

         temp=x[pivot];
         x[pivot]=x[j];
         x[j]=temp;
         quicksort(x,first,j-1);
         quicksort(x,j+1,last);

    }
}