【LeetCode】89. Gray Code解法及注释

89. Gray Code

Total
Accepted: 58433 Total
Submissions: 161645 Difficulty: Medium

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.

For example, given n = 2, return

[0,1,3,2]

. Its gray
code sequence is:

00 - 0
01 - 1
11 - 3
10 - 2

Note:

For a given n, a gray code sequence is not uniquely defined.

For example,

[0,2,3,1]

is also a valid gray code sequence according to the
above definition.

For now, the judge is able to judge based on one instance of gray code sequence. Sorry about that.
【分析】
题目很简单，给定二进制位数n，则对应数据范围：[0,(1<<n)-1]，一次循环遍历便可得到所有数据，由于只要求从0开始而不要求排序，满足要求的结果有很多种，但是目前LeetCode的测试案例库使能识别一种形式的解，所以不再深究：
【解法】

class Solution {
public:
vector<int> grayCode(int n) {
vector<int> result;
if(n<0)return result;
int maxValue;
maxValue=1<<n;
for(int i=0;i<maxValue;i++)
{
result.push_back(i);
}
return result;
}
};