Submission #1455634

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Source Code Expand

n = gets.chomp.to_i

dis = gets.chomp.split(" ").map(&:to_i)

dis.sort!

max_height = dis[0]

if dis[1] == max_height and n > 2
  puts "Impossible"
  exit(0)
end

if dis[-1] > max_height * 2
  puts "Impossible"
  exit(0)
end


level = {}

dis.each do |d|
  l = d - max_height
  level[l] = (level[l] || 0) + 1
end

(1..max_height).each do |l|
  if level[l] != 1 and level[l - 1] == 1
    puts "Impossible"
    exit(0)
  end
end

puts "Possible"

Submission Info

Judge Result