EasyNo. 2859
Sum of Values at Indices With K Set Bits — LeetCode 2859 Python Solution
- Pattern
- Bit Manipulation
- Topics
- Bit Manipulation, Array
- Reading time
- 2 min
- Source
- leetcode.com
The problem
You are given a 0-indexed integer array nums and an integer k. Return an integer that denotes the sum of elements in nums whose corresponding indices have exactly k set bits in their binary representation.
Example
- Input
- nums = [5,10,1,5,2], k = 1
- Output
- 13
- Explanation
- The binary representation of the indices are:
Python solution
class Solution:
def sumIndicesWithKSetBits(self, nums: List[int], k: int) -> int:
return sum(x for i, x in enumerate(nums) if i.bit_count() == k)Complexity
- Time
- O(n × log n)where n is the length of the array nums
- Space · auxiliary
- O(1)
Pattern: Bit Manipulation
Use XOR, masks and the low-bit trick to replace whole data structures with an integer. LeetCode 2859. Sum of Values at Indices With K Set Bits is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Bit Manipulation.
The bit manipulation guide has the Python template for the pattern and the 194 LeetCode problems that use it.
Related problems
| No. | Problem | Difficulty |
|---|---|---|
| 0136 | Single Number | Easy |
| 0137 | Single Number II | Medium |
| 0260 | Single Number III | Medium |
| 0287 | Find the Duplicate Number | Medium |
| 0318 | Maximum Product of Word Lengths | Medium |
| 0393 | UTF-8 Validation | Medium |
Frequently asked questions
- How hard is LeetCode 2859. Sum of Values at Indices With K Set Bits?
LeetCode 2859. Sum of Values at Indices With K Set Bits is rated Easy on LeetCode.
- What is the time complexity of LeetCode 2859. Sum of Values at Indices With K Set Bits?
The Python solution on this page runs in O(n × log n), where n is the length of the array nums.
- What is the space complexity of LeetCode 2859. Sum of Values at Indices With K Set Bits?
The Python solution on this page uses O(1) auxiliary space.
- What topics does LeetCode 2859. Sum of Values at Indices With K Set Bits cover?
LeetCode 2859. Sum of Values at Indices With K Set Bits is tagged Bit Manipulation and Array on LeetCode.