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New Hardware support: - IBM 653 Storage Unit: provides machine opcodes for Floating Point, Immediate Access Storage (IAS), Three Index registers, Cards Punch-read synchronizers 2 and 3. New Software included: - FORTRANSIT: version II (S), plus run time PACKAGE with standard Fortran functions. - Reorganized sw directory, separating each language in its own folder. Each one Includes a 00_readme.txt file with restoration notes and comments. New features: - Support for SOAP opcode mnemonics in addition to regular IBM mnemonics - FAST / REALTIME CPU options - PROP pseudo register - CARDDECK ECHOLAST command
35 lines
1005 B
Plaintext
35 lines
1005 B
Plaintext
c ------------------------------
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c prime number generator using the sieve of eratosthenes
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c converted to fortransit
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c ------------------------------
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c
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dimension ifl(50)
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c *** set ending number to be tested (must match array dimension)
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isize=50
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c *** mark all numbers in the sieve as prime initially, except 2
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do 10 i=1,isize
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10 ifl(i)=1
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ifl(1)=0
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c
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c *** work through the list, finding the next marked number
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c
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do 40 num=1,isize
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if (ifl(num)) 15,40,15
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c *** marked number is the current prime, form its first multiple
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15 iprme=num
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mult=iprme+iprme
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c *** unmark all multiples of the current prime
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20 if (mult-isize) 25,25,40
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25 do 30 i=mult,isize,iprme
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30 ifl(i)=0
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c *** go find next unmarked number
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40 continue
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c
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c *** print results - all numbers that are still marked
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c
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do 50 num=1,isize
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if (ifl(num)) 45,50,45
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45 punch, num
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50 continue
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end
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