notes/OJ notes/pages/Bit-Manipulation count true trick.md

Bit-Manipulation count true trick

2022-07-22 15:11

Algorithms:

#algorithm #bit_manipulation

Data Structure:

#DS #bitset

Difficulty:

#CS_analysis #difficulty-easy

Additional tags:

Related problems:

tag:#coding_problem tag:#bit_manipulation -tag:#template_remove_me 

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What is Bit-Manipulation count true trick?

(n & (n - 1))

How does Bit-Manipulation count true trick work?

validate if the number is power of 2

See Leetcode Power-of-Two#Method 1 using masking

Counting 1

See Leetcode Number-of-1-Bits#Method 2 n n - 1 method