Largest Combination With Bitwise AND Greater Than Zero Python/Java solution

In Python or Java, iterate through numbers and check each bit using shift operations. Maintain a 32-length array that counts occurrences of each bit. The answer is the maximum value in this array. The same logic translates directly to C++, C#, and JavaScript.

What is the best approach for Largest Combination With Bitwise AND Greater Than Zero?

The optimal approach is bit counting. Iterate through each of the 32 bit positions and count how many numbers in the array have that bit set. The maximum count represents the largest subset where the bitwise AND remains greater than zero. This runs in O(32 * n) time with O(1) extra space.

Is Largest Combination With Bitwise AND Greater Than Zero asked at Google/Amazon/Meta?

Bit manipulation and counting problems like this commonly appear in interviews at companies such as Amazon, Google, and Meta. The problem tests whether you can recognize patterns in bitwise operations and reduce subset problems into frequency counting.

What data structure is used in Largest Combination With Bitwise AND Greater Than Zero?

The solution mainly relies on simple counters or a fixed-size array of length 32 to track bit frequencies. No complex data structures are required; the problem focuses on bit manipulation and counting techniques.

What is the time complexity of Largest Combination With Bitwise AND Greater Than Zero?

The optimal solution runs in O(32 * n) time because each number is checked against 32 possible bit positions. Since 32 is constant for standard integers, the complexity is effectively O(n). Space complexity is O(1) because only a few counters are stored.

Description Hints 2 Solution Video 29:40

2275. Largest Combination With Bitwise AND Greater Than Zero

Q: Is Largest Combination With Bitwise AND Greater Than Zero easy or hard?

The problem is rated Medium on LeetCode. The implementation is straightforward once you realize that the AND result depends on shared bit positions, but identifying the bit-counting insight is the key step.

Q: How to solve Largest Combination With Bitwise AND Greater Than Zero in O(n)?

Treat each bit position independently. For every bit from 0 to 31, count how many numbers contain that bit using a shift operation like (num >> bit) & 1. The largest count among these positions represents the largest subset whose bitwise AND keeps that bit set. This yields an O(n) practical runtime since the number of bits is fixed.

Medium81.0% acceptance4 companies

The bitwise AND of an array nums is the bitwise AND of all integers in nums.

For example, for nums = [1, 5, 3], the bitwise AND is equal to 1 & 5 & 3 = 1.
Also, for nums = [7], the bitwise AND is 7.

You are given an array of positive integers candidates. Compute the bitwise AND for all possible combinations of elements in the candidates array.

Return the size of the largest combination of candidates with a bitwise AND greater than 0.

Example 1:

Input: candidates = [16,17,71,62,12,24,14]
Output: 4
Explanation: The combination [16,17,62,24] has a bitwise AND of 16 & 17 & 62 & 24 = 16 > 0.
The size of the combination is 4.
It can be shown that no combination with a size greater than 4 has a bitwise AND greater than 0.
Note that more than one combination may have the largest size.
For example, the combination [62,12,24,14] has a bitwise AND of 62 & 12 & 24 & 14 = 8 > 0.

Example 2:

Input: candidates = [8,8]
Output: 2
Explanation: The largest combination [8,8] has a bitwise AND of 8 & 8 = 8 > 0.
The size of the combination is 2, so we return 2.

Constraints:

1 <= candidates.length <= 10⁵
1 <= candidates[i] <= 10⁷

Asked at 4 companies

Jump Trading Adobe

Google Amazon

Topics

Hints open one at a time

Hint 1

For the bitwise AND to be greater than zero, at least one bit should be 1 for every number in the combination.

Hint 2

The candidates are 24 bits long, so for every bit position, we can calculate the size of the largest combination such that the bitwise AND will have a 1 at that bit position.

29:40

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