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mauvis
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Joined: 27 Jul 2007
Posts: 11
Location: india
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Can anyone tell me how we can find the prime number?
i need a simple logic...i need to accept a number through the JCL and have to check through cobol for prime no...
Mauvis |
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superk
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Joined: 26 Apr 2004
Posts: 4652
Location: Raleigh, NC, USA
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| A Google search led to this website which has an example program. |
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Balraj
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Joined: 16 Aug 2007
Posts: 34
Location: Bangalore
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Logic
Accept A
Perform varying i from 2 by 1 untill i > A
Divide A by i giving c remainder D
if D = 0
Not a prime
stop run
End-if
end-perform
A is a prime no.
stop run. |
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himanshupant
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Joined: 21 Mar 2007
Posts: 46
Location: India
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Just an afterthought , most of the times mainframe question / queries have some underlying Business requirement which needs to be satisfied , what was the business requirement behind this...
As for prime number bit , we can repeatedly divide the number ( Say x ) from 2 till x/2 and if in any of the case it divides exactly then its not a prime. We need not divide it till the number x.. This will reduce the number of iterations through loop
Correct me if I am wrong |
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guptae
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Joined: 14 Oct 2005
Posts: 1208
Location: Bangalore,India
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Hi himanshupant,
| Code: |
| As for prime number bit , we can repeatedly divide the number ( Say x ) from 2 till x/2 and if in any of the case it divides exactly then its not a prime. We need not divide it till the number x.. This will reduce the number of iterations through loop |
For prime number there is no need to divide till the number x/2 we can repeatedly divide the number til √x |
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guptae
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Joined: 14 Oct 2005
Posts: 1208
Location: Bangalore,India
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Hi All,
In my prev post i mean till square root of X |
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