#include<stdio.h>
#include<stdlib.h>

int sortfnc(const void *a,const void *b){
	if(*(int*)a == *(int*)b){return 0;}
	if(*(int*)a < *(int*)b){return -1;}
	return 1;
}

int main(void){
	int n,x[131072],i,min = 5000000;
	scanf("%d",&n);
	for(i = 0;i < n;i++){scanf("%d",&x[i]);}
	qsort(x,n,sizeof(int),sortfnc);
	if(n == 1){printf("0\n");return 0;}
	for(i = 0;i < n-1;i++){
		if(x[i] != x[i+1] && min > x[i+1] - x[i]){min = x[i+1] - x[i];}
	}
	if(min == 5000000){printf("0\n");}
	else{printf("%d\n",min);}
	return 0;
}