#!/usr/bin/env ruby

def valof(reg_file, reg_or_int)
  if reg_or_int >= 'a' && reg_or_int <= 'z' then
    return reg_file[reg_or_int] || 0
  end
  return reg_or_int.to_i
end

input = $stdin.readlines.map(&:chomp)

reg = {'a' => 1}
pc = 0

loop do
  break if pc < 0 || pc >= input.length
  istr = input[pc].split
  case istr[0]
  when 'set'
    reg[istr[1]] = valof(reg, istr[2])
  when 'sub'
    reg[istr[1]] = valof(reg, istr[1]) - valof(reg, istr[2])
  when 'mul'
    reg[istr[1]] = valof(reg, istr[1]) * valof(reg, istr[2])
  when 'jnz'
    if valof(reg, istr[1]) != 0 then
      pc += valof(reg, istr[2])
      pc -= 1
    end
  end
  pc += 1
end

puts reg['h']