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

t, rest = k.divmod(a + 1)

if (b - 1) < (a + 1)
  puts 1 + t * (a + 1) + rest
else
  if (b - 1) < a
    puts 1 + t * (b - 1) + rest
  else
    l, m = (k - a - 1).divmod(2)
    puts b + (b - a) * l + m
  end
end
