Dsa
Bit Manipulation
Hard
Count Unique Bit Patterns
Given an integer `n`, count the number of unique bit patterns that can be generated using exactly `k` bits set to 1. The value of `k` can range from 0 to the number of bits in `n`. You need to output the count of unique patterns.
Example:
Input:
12 2
Output:
6
// Explanation: 12 in binary is 1100. The unique patterns with exactly 2 bits set to 1 are: 1100, 1010, 1001, 0110, 0101, 0011.
Key concepts
bit_manipulationcountingcombinations
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