On the first row, we write a 0. Now in every subsequent row, we look at the previous row and replace each occurrence of 0 with 01, and each occurrence of 1 with 10.
Given row N and index K, return the K-th indexed symbol in row N. (The values of K are 1-indexed.) (1 indexed).
Examples:
Input: N = 1, K = 1
Output: 0
Input: N = 2, K = 1
Output: 0
Input: N = 2, K = 2
Output: 1
Input: N = 4, K = 5
Output: 1
Explanation:
row 1: 0
row 2: 01
row 3: 0110
row 4: 01101001
Note:
- N will be an integer in the range [1, 30].
- will be an integer in the range [1, 2^(N-1)].
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