K, A, B = gets.split.map(&:to_i)

if B - A <= 2
  puts K + 1
else
  exchange = (K - (A - 1)) / 2
  if ((K - (A - 1)) % 2 == 0)
    puts A + (B - A) * exchange
  else
    puts A + (B - A) * exchange + 1
  end
end
