#!/usr/bin/env ruby

input = gets.chomp.chars

ptr = 0
garbage = false
escape = false
lvl = 0
score = 0

input.each do |ch|
  if escape then
    escape = false
    next
  end
  
  if ch == '!' then
    escape = true
    next
  end

  if garbage then
    garbage = false if ch == '>'
    next
  end

  if ch == '<' then
    garbage = true
    next
  end

  if ch == '{' then
    lvl += 1
    score += lvl
    next
  end

  if ch == '}' then
    lvl -= 1
    next
  end
end

puts score