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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
#include <string>
#include <vector>
/* 変数i を n回繰り返すマクロ */
#define rep(i,n) for (int i = 0;i < (n);i++)
/* 配列の初期化 fill(array, 0); すべて0に初期化 */
template<typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val){std::fill( (T*)array, (T*)(array+N), val );}
using namespace std;
int main()
{
    long long n,a,b;
    cin >> n >> a >> b;

    long long waru = n / (a + b);
    long long amari = n % (a + b);

    if(amari > a){
        amari = 0;
    }

    long ans = waru * a + amari;

    cout << ans << endl;

    return 0;
}