public class Solution
extends Object
779 - K-th Symbol in Grammar\.
Medium
We build a table of `n` rows ( **1-indexed** ). We start by writing `0` in the 1st row. 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`.
* For example, for `n = 3`, the 1st row is `0`, the 2nd row is `01`, and the 3rd row is `0110`.
Given two integer `n` and `k`, return the kth ( **1-indexed** ) symbol in the nth row of a table of `n` rows.
**Example 1:**
**Input:** n = 1, k = 1
**Output:** 0
**Explanation:** row 1: 0
**Example 2:**
**Input:** n = 2, k = 1
**Output:** 0
**Explanation:** row 1: 0 row 2: 01
**Example 3:**
**Input:** n = 2, k = 2
**Output:** 1
**Explanation:** row 1: 0 row 2: 01
**Constraints:**
* `1 <= n <= 30`
* 1 <= k <= 2n - 1