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 Rust (1.15.1) (judge verdict: Accepted)

macro_rules! input {
    ($ttype:ty) => {
        {
            let mut input = String::new();
            let _= std::io::stdin().read_line(&mut input);
            input.trim().parse::<$ttype>().unwrap()
        }
    };

    ($($ttype:ty),*) => {
        {
            use std::io::BufRead;
            let mut input = String::new();
            let stdin = std::io::stdin();
            let _ = stdin.lock().read_line(&mut input);
            let mut iter = input.trim().split_whitespace();
            (
                $(iter.next().unwrap().parse::<$ttype>().unwrap(),)*
            )
        }
    };

    ($ttype:ty; $x:expr) => {
        {
            use std::io::BufRead;
            let mut input = String::new();
            let stdin = std::io::stdin();
            let _ = stdin.lock().read_line(&mut input);
            let v: Vec<$ttype> = input
                .trim()
                .split_whitespace()
                .map(|x| x.parse().unwrap())
                .collect();
            v
        }
    };

    ($ttype:ty; $x:expr; $y:expr) => {
        {
            use std::io::BufRead;
            let mut matrix = Vec::with_capacity($y);
            for _ in 0..$y {
                let mut input = String::new();
                let stdin = std::io::stdin();
                let _ = stdin.lock().read_line(&mut input);
                let v: Vec<$ttype> = input
                    .trim()
                    .split_whitespace()
                    .map(|x| x.parse().unwrap())
                    .collect();
                matrix.push(v);
            }
            matrix
        }
    };
}

fn main() {
    let mut n = input!(i64);
    let mut i: u32 = 0;
    let mut zero_or_one: Vec<i32> = Vec::with_capacity(64);

    if n == 0 {
        println!("0");
        return;
    }

    while n != 0 {
        if n % (-2i64).pow(i+1) != 0 {
            zero_or_one.push(1);
            n -= (-2i64).pow(i);
        } else {
            zero_or_one.push(0);
        }
        i += 1;
    }

    zero_or_one.reverse();
    // zero_or_one.iter().for_each(move |x| print!("{}", x));
    for bit in zero_or_one.iter() {
        print!("{}", bit);
    }
    println!("");
}