n=int(input())
ls=list(map(int,input().split()))
ls.sort()
lsdis=[]
for i in range(n-1):
  lsdis.append(ls[i+1]-ls[i])
lsnew=[]
for i in range(len(lsdis)):
    if lsdis[i]!=0:
        lsnew.append(lsdis[i])
if len(lsnew)==0:
  print(0)
else:
  print(min(lsnew))