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>
using namespace std;
#define REP(i,n) for(int i=0; i<(int)(n); i++)
#define RNG(i,from,to) for(int i=(from); i<(int)(to); i++)
#define gcd(i,j) __gcd((i), (j))
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<ll> vecll;
template<typename S, typename T> string to_string(pair<S, T> p) { return "("+to_string(p.first)+","+to_string(p.second)+")"; }
template<typename T> string to_string(T p[2]) { return "["+to_string(p[0])+","+to_string(p[1])+"]"; }
template<typename T> void println(T e){ cout << to_string(e) << endl; }
template<typename T> void println(const vector<T>& v){ cout << "[";for(const auto& e : v){ cout << to_string(e) << ","; }cout << "]";cout << endl; }
template<typename T> void println(const vector<vector<T>>& vv){ for(const auto& v : vv){ println(v); } }
template<typename Iter> void println(Iter first, Iter last){ for(auto it=first; it != last; it++){ cout << *it << " "; }; cout << endl; }
template<typename T> T mod_pow(T x, T n, const T &p) { T ret = 1; while(n > 0) { if(n & 1) (ret *= x) %= p; (x *= x) %= p; n >>= 1; } return ret; }
template<typename T> T mod_inv(T x, const T &p) { return mod_pow(x, p-2, p); }
const ll DVSR = 1e9+7;


int main(int argc, char const *argv[])
{
  ll N, A, B; cin >> N >> A >> B;
  cout << (N / (A+B))*A + min(N % (A+B), A) << endl;
  return 0;
}