Blum integer: Difference between revisions
Content added Content deleted
(→{{header|C}}: Specialized primeFactors routine - about 20% faster than before.) |
(→{{header|Wren}}: Optimized - about 30% faster than before.) |
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import "./fmt" for Fmt |
import "./fmt" for Fmt |
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var |
var inc = [4, 2, 4, 2, 4, 6, 2, 6] |
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// Assumes n is odd. |
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var firstPrimeFactor = Fn.new { |n| |
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if (n == 1) return 1 |
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if (n%3 == 0) return 3 |
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if (n%5 == 0) return 5 |
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var k = 7 |
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var i = 0 |
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while (k * k <= n) { |
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| ⚫ | |||
return k |
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} else { |
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k = k + inc[i] |
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i = (i + 1) % 8 |
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} |
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} |
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return n |
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} |
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var blum = List.filled(50, 0) |
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var bc = 0 |
var bc = 0 |
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var counts = { 1: 0, 3: 0, 7: 0, 9: 0 } |
var counts = { 1: 0, 3: 0, 7: 0, 9: 0 } |
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var i = 1 |
var i = 1 |
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while (true) { |
while (true) { |
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var |
var p = firstPrimeFactor.call(i) |
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if ( |
if (p % 4 == 3) { |
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var q = i / p |
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if (q != p && q % 4 == 3 && Int.isPrime(q)) { |
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bc |
if (bc < 50) blum[bc] = i |
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counts[i % 10] = counts[i % 10] + 1 |
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bc = bc + 1 |
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if (bc == 50) { |
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System.print() |
System.print("First 50 Blum integers:") |
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Fmt.tprint("$3d ", blum, 10) |
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System.print() |
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if (bc == |
} else if (bc == 26828 || bc % 1e5 == 0) { |
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Fmt.print("The $,9r Blum integer is: $,9d", bc, i) |
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if (bc == 400000) { |
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System.print("\n\% distribution of the first 400,000 Blum integers:") |
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for (i in [1, 3, 7, 9]) { |
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Fmt.print(" $6.3f\% end in $d", counts[i]/4000, i) |
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} |
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return |
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} |
} |
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| ⚫ | |||
} |
} |
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} |
} |
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The 400,000th Blum integer is: 8,802,377 |
The 400,000th Blum integer is: 8,802,377 |
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% distribution of the first 400,000 Blum integers: |
% distribution of the first 400,000 Blum integers is: |
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25.001% end in 1 |
25.001% end in 1 |
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25.017% end in 3 |
25.017% end in 3 |
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24.997% end in 7 |
24.997% end in 7 |
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24.985% end in 9 |
24.985% end in 9 |
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</pre> |
</pre> |
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