Problem:
Score : 200 points

Problem Statement

Takahashi has many red balls and blue balls. Now, he will place them in a row.

Initially, there is no ball placed.

Takahashi, who is very patient, will do the following operation 10^{100} times:

Place A blue balls at the end of the row of balls already placed. Then, place B red balls at the end of the row.

How many blue balls will be there among the first N balls in the row of balls made this way?

Constraints

1 \leq N \leq 10^{18}

A, B \geq 0

0 < A + B \leq 10^{18}

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N A B

Output

Print the number of blue balls that will be there among the first N balls in the row of balls.

Sample Input 1

8 3 4

Sample Output 1

4

Let b denote a blue ball, and r denote a red ball. The first eight balls in the row will be bbbrrrrb, among which there are four blue balls.

Sample Input 2

8 0 4

Sample Output 2

0

He placed only red balls from the beginning.

Sample Input 3

6 2 4

Sample Output 3

2

Among bbrrrr, there are two blue balls.

Solution in Haskell (GHC 7.10.3) (judge verdict: Accepted)

countBlue :: Integer -> Integer -> Integer -> Integer
countBlue n a b = let (d,m) = n `divMod` (a+b) in (a*d) + (minimum [a,m])
--   | n > a+b   = a + (countBlue (n-a-b) a b)
--   | n < a     = n
--   | otherwise = a

main = do
   [n,a,b] <- map read . words <$> getLine
   putStrLn $ show $ countBlue n a b