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: Accepted)

#include<bits/stdc++.h>
#define VI vector<int>
#define VVI vector<vector<int>>
#define REP(i,n) for(int i=0;i<(n);i++)
#define MOD 1000000007
#define INF 1e9
#define All(x) (x).begin(),(x).end()
typedef long long ll;
using namespace std;

int main(){
  ll N,A,B;
  cin>>N>>A>>B;
  ll cnt=N/(A+B);
  ll ans=cnt*A;
  ll a=N-cnt*(A+B);
  ans+=min(A,a);
  cout<<ans<<endl;
}