def combi(n,k)
  sum = 1
  (n-k).times do|i|
    sum = sum*(i + k+1)
  end
  return sum
end

n = gets.chomp.to_i
s = []
n.times do
  s << gets.chomp
end

hash = {"a"=>0, "b"=>0, "c"=>0, "d"=>0, "e"=>0, "f"=>0, "g"=>0, "h"=>0, "i"=>0, "j"=>0, "k"=>0, "l"=>0, "m"=>0, "n"=>0, "o"=>0, "p"=>0, "q"=>0, "r"=>0, "s"=>0, "t"=>0, "u"=>0, "v"=>0, "w"=>0, "x"=>0, "y"=>0, "z"=>0}

hash_arr = []
count_arr = []

pos_arr=[]

n.times do|i|
  a = hash.dup
  s[i].each_char do|c|
    a[c] += 1
  end
  #puts "now a = #{a}"
  flag = 1
  (hash_arr.length).times do |j|
    if(hash_arr[j] == a) then
      flag = 0
      count_arr[j] += 1
      break
    end
  end
  if(flag == 1) then
    hash_arr << a.dup
    count_arr << 0
    pos_arr << i
  end
end

#puts "count_arr = #{count_arr}"
sum = 0
count_arr.each do|el|
  if(el != 0) then
    sum += combi( (el+1), 2)
  end
end
puts sum