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

x = 0

if a+2 > b
    k -= b
    x += a+2
elsif
    if k >= a+1
        k -= a+1
        x += b
    end
end

if a+1 > b
    x += k
elsif
    x += (k / (a+2)) * b
    x += k % (a+2)
end

puts x
