In the Bitwise Kingdom, located somewhere in the universe, there are exactly 2N citizens living and each of them has a unique identification string that represents his or her class in the society. An identification string is a binary string of length N which consists of characters ‘0’ or ‘1’. The order of classes is defined among the citizens by the following criteria:
For example, if N = 3, there are 8 (= 23) people in the country, and their identification strings are “000â€, “001â€, “010â€, “100â€, “011â€, “101â€, “110â€, and “111†(from the lowest class to the highest).
You are given two numbers N (1 ≤ N ≤ 60) and M (1 ≤ M ≤ 2N), and you want to resolve the identification string of the person of the M-th lowest class among 2N citizens. Can you write a program to solve this problem?
The input consists of multiple datasets.
Each dataset consists of a line which contains two integers N and M in this order, separated with a single space. The input does not contain any other extra characters such as leading or trailing spaces.
The end of input is indicated by a line with two zeros. This line is not part of any datasets.
For each dataset, print the identification string of the person of the M-th lowest class in one line. Your program may not omit any leading zeros in the answer.
3 3 3 5 0 0
010 011