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: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AtCoder.Abc
{
    //https://atcoder.jp/contests/abc158/tasks/abc158_b
    class QuestionB
    {
        public static void Main(string[] args)
        {
            var sw = new System.IO.StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
            Console.SetOut(sw);

            // 整数配列の入力
            var inputLongArray = Console.ReadLine().Split(' ').Select(i => long.Parse(i)).ToArray();
            long n = inputLongArray[0];
            long a = inputLongArray[1];
            long b = inputLongArray[2];
            long ans = 0;
            if (a == 0)
            {
                Console.WriteLine(0);
                Console.Out.Flush();
            }
            else
            {
                ans = (n / (a + b))*a;
                long amari = (n % (a + b));
                if (a >= amari)
                {
                    ans += amari;
                }
                else
                {
                    ans += a;
                }
            }


            Console.WriteLine(ans);

            Console.Out.Flush();
        }
    }
}