#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
a=list(a)
a.sort()
diff=abs(a[1]-a[0])
for i in range(2,n):
      if (abs(a[i] - a[i-1]) < diff):
          diff = abs(a[i] - a[i-1])
print diff
# your code goes here