k, a, b = gets.split(' ')
k = k.to_i ; a = a.to_i ; b = b.to_i
cookie = 1
if (b - a) <= 1 || (a - k) >= 0
  cookie = cookie + k
elsif (a - k) == -1
  cookie = [b,k+1].max
else
  # step 1
  k = k - (a - 1)
  cookie = cookie + (a - 1)
  
  # step 2
  k = k - 1

  # step 3
  k = k - 1
  cookie = b
  
  # step 3
  cookie = cookie + ((b - a) * (k / 2))
  cookie = cookie + 1 if k.odd?
end

puts cookie