Blum integer: Difference between revisions
Content added Content deleted
(→{{header|C}}: Updated in line with Wren example - run time now under 1 second.) |
(→{{header|Go}}: Updated in line with Wren example of which it is a translation.) |
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"rcu" |
"rcu" |
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) |
) |
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var inc = []int{4, 2, 4, 2, 4, 6, 2, 6} |
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// Assumes n is odd. |
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func firstPrimeFactor(n int) int { |
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if n == 1 { |
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return 1 |
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} |
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if n%3 == 0 { |
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return 3 |
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} |
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if n%5 == 0 { |
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return 5 |
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} |
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for k, i := 7, 0; k*k <= n; { |
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if n%k == 0 { |
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| ⚫ | |||
} else { |
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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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func main() { |
func main() { |
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i := 1 |
i := 1 |
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for { |
for { |
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p := firstPrimeFactor(i) |
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if |
if p%4 == 3 { |
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q := i / p |
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if q != p && q%4 == 3 && rcu.IsPrime(q) { |
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if bc < 50 { |
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blum[bc] = i |
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} |
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counts[i%10/3]++ |
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bc++ |
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if bc == 50 { |
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fmt.Println() |
fmt.Println("First 50 Blum integers:") |
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rcu.PrintTable(blum, 10, 3, false) |
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fmt.Println() |
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if bc == |
} else if bc == 26828 || bc%100000 == 0 { |
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fmt. |
fmt.Printf("The %7sth Blum integer is: %9s\n", rcu.Commatize(bc), rcu.Commatize(i)) |
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if bc == 400000 { |
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fmt.Println("\n% distribution of the first 400,000 Blum integers:") |
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digits := []int{1, 3, 7, 9} |
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for j := 0; j < 4; j++ { |
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fmt.Printf(" %6.3f%% end in %d\n", float64(counts[j])/4000, digits[j]) |
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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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