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;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace AtCoder
{
	public class ABC
	{
		private const int mod = 1000000007;  // 10^9+7

		static void Main(string[] args)
		{
			//System.Diagnostics.Stopwatch stopwatch = new System.Diagnostics.Stopwatch(); stopwatch.Start();
			Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });


			//string s = Console.ReadLine();
			//int n = int.Parse(Console.ReadLine());
			//long x = long.Parse(Console.ReadLine());
			//int[] vs = Console.ReadLine().Split().Select(int.Parse).ToArray();
			long[] vs = Console.ReadLine().Split().Select(long.Parse).ToArray();
			long n = vs[0];
			long a = vs[1];
			long b = vs[2];
			long ans = 0;

			long x = n / (a + b);
			ans += a * x;
			long y = n % (a + b);
			if (y < a) {
				ans += y;
			} else {
				ans += a;
			}
			Console.WriteLine(ans);


			Console.Out.Flush();
			//System.Diagnostics.Debug.WriteLine(stopwatch.Elapsed);
		}
	}
}