#include<stdio.h>
#include<math.h>
int main(){
	int i,j,k=0,n;
	scanf("%d",&n);
	long int a[n],diff[n],x[n],smallest=1000000000;
	for(i=0;i<n;i++)
	scanf("%ld",&a[i]);
	for(i=0;i<n;i++)
	{
		for(j=i;j<n-1;j++)
		{
			diff[k]=a[i]-a[j+1];
			x[k]=abs(diff[k]);
			k++;
		}
		if(smallest>x[i])
			smallest=x[i];
	}
	printf("%ld",smallest);
	return 0;
}