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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

namespace ABC158b
{
    class Program
    {
        static void Main(string[] args)
        {
            var s = Console.ReadLine().Split(' ');
            long N = long.Parse(s[0]);
            long A = long.Parse(s[1]);
            long B = long.Parse(s[2]);

            if (A == 0)
            {
                Console.WriteLine(0);
                return;
            }

            long t = N / (A + B);
            long C1 = t * A;

            long v = N % (A + B);

            long C2 = v;
            if (v >= A)
            {
                C2 = A;
            }
            Console.WriteLine(C1 + C2);
        }
    }
}