import strutils, sequtils, algorithm, math

var
  n = readLine(stdin).parseInt
  x_seq = split(readLine(stdin), ' ').map(parseInt)
  min_v = high(int)
  flag = true

x_seq.sort(cmp[int])

for i in countup(0, x_seq.len() - 2):
  if x_seq[i] == x_seq[i + 1]:
    continue
  min_v = min(min_v, max(abs(x_seq[i] - x_seq[i + 1]), 1))
  flag = false

if flag:
  min_v = 0

echo(min_v)