Square-free integers: Difference between revisions
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Thundergnat (talk | contribs) m (→{{header|Perl 6}}: Minor tweaks.) |
m (→{{header|FreeBASIC}}: changed indents) |
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For i = 4 To max Step 2 ' prime sieve remove even numbers except 2 |
For i = 4 To max Step 2 ' prime sieve remove even numbers except 2 |
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sieve(i) = 1 |
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Next |
Next |
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For i = 3 To stop_ Step 2 ' proces odd numbers |
For i = 3 To stop_ Step 2 ' proces odd numbers |
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If sieve(i) = 0 Then |
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For a = i * i To max Step i * 2 |
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sieve(a) = 1 |
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Next |
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End If |
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Next |
Next |
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For i = 2 To max ' move primes to a list |
For i = 2 To max ' move primes to a list |
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If sieve(i) = 0 Then |
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c += 1 |
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prime(c) = i |
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End If |
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Next |
Next |
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For i = 1 To c ' find all square free integers between 1 and 1000000 |
For i = 1 To c ' find all square free integers between 1 and 1000000 |
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a = prime(i) * prime(i) |
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If a > 1000000 Then Exit For |
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For k = a To 1000000 Step a |
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list(k) = 1 |
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Next |
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Next |
Next |
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k = 0 |
k = 0 |
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For i = 1 To 145 ' show all between 1 and 145 |
For i = 1 To 145 ' show all between 1 and 145 |
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If list(i) = 0 Then |
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Print Using"####"; i; |
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k +=1 |
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If k Mod 20 = 0 Then Print |
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End If |
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Next |
Next |
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Print : Print |
Print : Print |
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sieve(0) = 1 ' = trillion |
sieve(0) = 1 ' = trillion |
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For i = 1 To 5 ' process primes 2, 3, 5, 7, 11 |
For i = 1 To 5 ' process primes 2, 3, 5, 7, 11 |
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a = prime(i) * prime(i) |
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b = a - trillion Mod a |
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For k = b To 145 Step a |
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sieve(k) = 1 |
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Next |
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Next |
Next |
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For i = 6 To c ' process the rest of the primes |
For i = 6 To c ' process the rest of the primes |
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a = prime(i) * prime(i) |
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k = a - trillion Mod a |
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If k <= 145 Then sieve(k) = 1 |
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Next |
Next |
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k = 0 |
k = 0 |
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For i = 0 To 145 |
For i = 0 To 145 |
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If sieve(i) = 0 Then |
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Print Using "################"; (trillion + i); |
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k += 1 |
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If k Mod 5 = 0 Then print |
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End If |
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Next |
Next |
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Print : Print |
Print : Print |
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a = 1 : b = 100 : k = 0 |
a = 1 : b = 100 : k = 0 |
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Do Until b > 1000000 ' count them |
Do Until b > 1000000 ' count them |
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For i = a To b |
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If list(i) = 0 Then k += 1 |
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Next |
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Print "There are "; k; " square free integers between 1 and "; b |
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a = b : b *= 10 |
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Loop |
Loop |
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