2595

2595. Number of Even and Odd Bits (Easy)

You are given a positive integer n.

Let even denote the number of even indices in the binary representation of n (0-indexed) with value 1.

Let odd denote the number of odd indices in the binary representation of n (0-indexed) with value 1.

Return an integer array answer where answer = [even, odd].

 

Example 1:

Input: n = 17
Output: [2,0]
Explanation: The binary representation of 17 is 10001. 
It contains 1 on the 0th and 4th indices. 
There are 2 even and 0 odd indices.

Example 2:

Input: n = 2
Output: [0,1]
Explanation: The binary representation of 2 is 10.
It contains 1 on the 1st index. 
There are 0 even and 1 odd indices.

 

Constraints:

• 1 <= n <= 1000

Related Topics:
Bit Manipulation

Similar Questions:

• Find Numbers with Even Number of Digits (Easy)

Solution 1.

// OJ: https://leetcode.com/problems/number-of-even-and-odd-bits
// Author: github.com/lzl124631x
// Time: O(logN)
// Space: O(1)
class Solution {
public:
    vector<int> evenOddBit(int n) {
        vector<int> ans(2);
        for (int i = 0; n; n >>= 1, i = 1 - i) {
            ans[i] += (n & 1);
        }
        return ans;
    }
};