k, a, b = gets.chomp.split.map(&:to_i)

if b - a <= 2
  puts k + 1
elsif a >= k
  puts k + 1
else
  r = k - a + 1
  c = r / 2

  if r.even?
    puts (c - 1) * (b - a) + b
  else
    puts (c - 1) * (b - a) + b + 1
  end
end
