#!/bin/ruby

n = gets.strip.to_i
a = gets.strip
a = a.split(' ').map(&:to_i)
# your code goes here
min = nil

a.sort!

(0...(n - 1)).each do |i|
    diff = (a[i] - a[i + 1]).abs
    min = diff if min.nil? || diff < min
end

puts min