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 Python (3.4.3) (judge verdict: Accepted)

n = int(input())

def plus(k):
    j = 0
    while (2**(j+2) - 1)/3 < k:
        j += 2
    return 10**j,k-2**j

def minus(k):
    j = 1
    while ((-2)**(j+2)-(-2))/3 > k:
        j += 2
    return 10**j,k-(-2)**j

ans = 0    
while n != 0:
    if n > 0:
        a,n = plus(n)
        ans += a
    else:
        a,n = minus(n)
        ans += a

print(ans)