def hitung_jarak_kluster cluster1, cluster2
  #p cluster1, cluster2
    jarak = 0;
    cluster1.each do |a|
        cluster2.each do |b|
            jarak +=Math.sqrt ( a.zip(b).map{ |n| n.reduce(:-)}.map{|n| n**2}.reduce(:+) )
        end
    end
    jarak
end
data = [ [1,1] ,[2,1], [2,2], [1,2], [7,7], [9,9]]
cluster = Hash.new
data.each {|arr| cluster[arr] = [arr] }
k = gets.chomp.to_i
n = data.length
while n != k
    min = 999999
    join = []
    cluster.each do|k,v|
        cluster.each do|i,p|
            if (p != v)
                temp = hitung_jarak_kluster v,p
        join = [k,i] if (temp < min)
                min = temp if (temp < min)
            end
        end
    end
    cluster[join[0]] = cluster[join[0]] + cluster[join[1]]
    cluster.delete( join[1] )
    n-=1
end
p cluster