#!/bin/ruby
# your code goes here
n = gets.strip.to_i
a = gets.strip
a = a.split(' ').map(&:to_i)
a = a.sort
i = a.length - 1
min_diff = (a[-1] - a[0]).abs # should be max diff so good place to start, also deals with case where length of a is 1
while i > 0
    diff = (a[i] - a[i-1]).abs
    min_diff = diff if diff < min_diff
    i -= 1
end
p min_diff