Problem:
Score : 300 points

Problem Statement

Given an integer N, find the base -2 representation of N.

Here, S is the base -2 representation of N when the following are all satisfied:

S is a string consisting of 0 and 1.

Unless S = 0, the initial character of S is 1.

Let S = S_k S_{k-1} ... S_0, then S_0 \times (-2)^0 + S_1 \times (-2)^1 + ... + S_k \times (-2)^k = N.

It can be proved that, for any integer M, the base -2 representation of M is uniquely determined.

Constraints

Every value in input is integer.

-10^9 \leq N \leq 10^9

Input

Input is given from Standard Input in the following format:

N

Output

Print the base -2 representation of N.

Sample Input 1

-9

Sample Output 1

1011

As (-2)^0 + (-2)^1 + (-2)^3 = 1 + (-2) + (-8) = -9, 1011 is the base -2 representation of -9.

Sample Input 2

123456789

Sample Output 2

11000101011001101110100010101

Sample Input 3

0

Sample Output 3

0

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

//https://atcoder.jp/contests/abc105/tasks/abc105_c

import java.io.*;
import java.util.ArrayList;

class Main{
    ArrayList<String> ans = new ArrayList<>();
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String str = br.readLine();
        long N = Long.parseLong(str);
        StringBuffer ans = new StringBuffer();
        while (N!=0){
            if (N%2==0){
                ans.insert(0, "0");
            } else {
                N--;
                ans.insert(0, "1");
            }
            N /= -2;
        }
        if (ans.length()==0){
            ans.append("0");
        }
        System.out.println(ans);
    }
}