feat: add count distinct primes from binary string algorithm #2970
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Add count_distinct_primes_from_binary_string.cpp
rudrakshtank
requested review from
Panquesito7 and
realstealthninja
as code owners
| #include <unordered_set> | ||
| #include <algorithm> | ||
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| const int MAX = 1e6; |
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max cannot be a negative number, hence replace int with uint32_t
| #include <algorithm> | ||
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| const int MAX = 1e6; | ||
| std::vector<bool> is_prime; |
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| std::vector<bool> is_prime; | |
| static std::vector<bool> is_prime; | |
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Since you want to pre compute primes why not make this a constexpr? and assign in it directly? instead of a call from main. Also afaik vectors cant be used as constexpr in c++17 hence it might be preferred if you use std::array instead.
if any of this sounds confusing let me know I can explain or direct you to resources to learn about this feature of c++
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| return cnt; | ||
| } | ||
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| } // bit_manipulation |
| std::unordered_set<int> seen; | ||
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| for (int i = 2; i < limit; i++) { | ||
| if (__builtin_popcount(i) <= k && is_prime[i]) { |
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__builtin_popcount is not part of the STL library it only exists in GCC.
thus this should be replaced with std::popcount()
| if (__builtin_popcount(i) <= k && is_prime[i]) { | |
| if (std::popcount(i) <= k && is_prime[i]) { | |
| #include <iostream> | ||
| #include <vector> | ||
| #include <unordered_set> | ||
| #include <algorithm> |
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| #include <iostream> | |
| #include <vector> | |
| #include <unordered_set> | |
| #include <algorithm> | |
| #include <bit> /// for std::popcount | |
| #include <iostream> | |
| #include <vector> | |
| #include <unordered_set> | |
| #include <algorithm> |
| return cnt; | ||
| } | ||
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| /** |
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please add tests here
realstealthninja
changed the title
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Thank you for the review, I'll get back to you with suggested changes |
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I have done with the suggested changes, please review the changes |
@realstealthninja Could you please review this PR?
Description of Change
Added
count_distinct_primes_from_binary_string.cppto thebit_manipulation/directory.This program counts the number of distinct prime numbers that can be formed from a binary string using:
It uses an efficient implementation of the Sieve of Eratosthenes for prime checking and bitmasking to explore all possible combinations.
Includes:
main()with an example test caseContributors guide
Checklist
main()Notes:
Efficient bitmask + sieve-based solution to find all valid prime numbers from binary strings using allowed transformations.