q(const void *a,const void *b){return *(int*)a-*(int*)b;}main(n,i,m,t){int x[100000];m=1000001;scanf("%d",&n);for(i=0;i<n;i++)scanf("%d",&x[i]);qsort(x,n,sizeof(int),q);for(i=0;i<n-1;i++){t=abs(x[i]-x[i+1]);t<m&&t>0?m=t:0;}printf("%d",m<1000001?m:0);}