The gray code is a binary numeral system where two successive values differ in only one bit.
Given a non-negative integer n representing the total number of bits in the code, print the sequence of gray code. A gray code sequence must begin with 0.
Example 1:
Input: 2
Output: [0,1,3,2]
Explanation:
00 - 0
01 - 1
11 - 3
10 - 2
For a given n, a gray code sequence may not be uniquely defined.
For example, [0,2,3,1] is also a valid gray code sequence.
00 - 0
10 - 2
11 - 3
01 - 1
Example 2:
Input: 0
Output: [0]
Explanation: We define the gray code sequence to begin with 0.
A gray code sequence of n has size = 2n, which for n = 0 the size is 20 = 1.
Therefore, for n = 0 the gray code sequence is [0].
格雷编码是一个二进制数字系统,在该系统中,两个连续的数值仅有一个位数的差异。给定一个代表编码总位数的非负整数 n,打印其格雷编码序列。格雷编码序列必须以 0 开头。
- 输出 n 位格雷码
- 格雷码生成规则:以二进制为0值的格雷码为第零项,第一次改变最右边的位元,第二次改变右起第一个为1的位元的左边位元,第三、四次方法同第一、二次,如此反复,即可排列出 n 个位元的格雷码。
- 可以直接模拟,也可以用递归求解。