Substring primes: Difference between revisions
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m (→{{header|ALGOL 68}}: The sieve generated by PRIMESIEVE now includes 0) |
Alextretyak (talk | contribs) (Added 11l) |
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Solve by testing at most 15 numbers for primality. Show a list of all numbers tested that were not prime. |
Solve by testing at most 15 numbers for primality. Show a list of all numbers tested that were not prime. |
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<br><br> |
<br><br> |
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=={{header|11l}}== |
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{{trans|Go}} |
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<lang 11l>F is_prime(n) |
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I n == 2 |
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R 1B |
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I n < 2 | n % 2 == 0 |
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R 0B |
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L(i) (3 .. Int(sqrt(n))).step(2) |
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I n % i == 0 |
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R 0B |
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R 1B |
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V results = [2, 3, 5, 7] |
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V odigits = [3, 7] |
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[Int] discarded |
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V tests = 4 |
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V i = 0 |
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L i < results.len |
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V r = results[i] |
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i++ |
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L(od) odigits |
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I (r % 10) != od |
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V n = r * 10 + od |
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I is_prime(n) |
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results.append(n) |
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E |
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discarded.append(n) |
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tests++ |
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print(‘There are ’results.len‘ primes where all substrings are also primes, namely:’) |
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print(results) |
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print("\nThe following numbers were also tested for primality but found to be composite:") |
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print(discarded) |
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print("\nTotal number of primality tests = "tests)</lang> |
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{{out}} |
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<pre> |
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There are 9 primes where all substrings are also primes, namely: |
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[2, 3, 5, 7, 23, 37, 53, 73, 373] |
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The following numbers were also tested for primality but found to be composite: |
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[27, 57, 237, 537, 737, 3737] |
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Total number of primality tests = 15 |
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</pre> |
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=={{header|Action!}}== |
=={{header|Action!}}== |