Is probable prime #32
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faheel
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faheel
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@KingAkeem Sorry for the late review. If you're still interested in working on this then please make the following changes. Otherwise, just let me know and I'll either complete this myself or assign it to someone else.
| num = 3; | ||
| REQUIRE(num.is_probable_prime(25) == 1); | ||
| num = 5; | ||
| REQUIRE(num.is_probable_prime(25) == 1); |
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What about larger cases? Can you check that it returns true for the following prime numbers:
- 4361161843811
- 91584398720031
- 54362229927468991056799869539182953179604007
- 1141606828476848812192797260322842016771684147
- 237082482904158189833801188468727382999221896206963750677
- 4978732140987321986509824957843275042983659820346238764217
and false for the following composite numbers:
- 576308207413
- 648273642634986
- 328964398726983264982
- 4079327665427094820942557
- 879654387682647825646328764
- 98732243986019286982046325298743
- 589658224987973265974369876397863298796328749
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I can't test because Binary Arithmetic Tests are failing
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This is because a is not declared. I think you forgot to replace all instances of a to rand_num.
test/functions/math.cpp
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| BigInt num = 11; | ||
| REQUIRE(pow(num, 9) == 2357947691); | ||
| BigInt num = 11; | ||
| REQUIRE(pow(num, 9) == 2357947691); |
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Please indent your code with 4 spaces per level.
include/functions/utility.hpp
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| s++; | ||
| long long spower = pow(2, s); | ||
| if (spower > sentinel_value) { | ||
| return std::make_tuple(0,0); |
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Please indent your code with 4 spaces per level.
include/functions/math.hpp
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| bool BigInt::is_probable_prime(size_t certainty) { | ||
| // The BigInt object that this method refers to will be referred to as n in comments | ||
| #define COMPOSITE false | ||
| #define PRIME true |
include/functions/math.hpp
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| BigInt a; | ||
| while (certainty-- > 0) { | ||
| // 1 <= a < n | ||
| a = random_number(); |
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Rename a to rand_num, and random_number to get_random_number.
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Some cases fail: |
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Going to take a lot at this again soon |
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#5 I've added the is_probable_prime method using Rabin Miller primality testing. I started with Little Fermat's Theorem and built from that. I also had to add a utility function in order to calculate much needed values. I've added a test to cover the base cases but I've ran a number of test using extremely large primes and a variety random primes using random generators. The test is fast and very accurate based on the certainty passed to it.