35 lines
942 B
Text
35 lines
942 B
Text
BEGIN
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# returns TRUE if n is prime, FALSE otherwise #
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PROC is prime = ( LONG INT n )BOOL:
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IF n MOD 2 = 0 THEN n = 2
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ELIF n MOD 3 = 0 THEN n = 3
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ELSE
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LONG INT d := 5;
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BOOL result := TRUE;
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WHILE IF d * d > n THEN FALSE
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ELIF n MOD d = 0 THEN result := FALSE
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ELIF d +:= 2;
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n MOD d = 0 THEN result := FALSE
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ELSE d +:= 4; TRUE
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FI
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DO SKIP OD;
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result
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FI # is prime # ;
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LONG INT i := 42;
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LONG INT n := 0;
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WHILE n < 42 DO
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IF is prime( i ) THEN
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n +:= 1;
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print( ( "n = "
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, whole( n, -2 )
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, " "
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, whole( i, -19 )
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, newline
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)
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);
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i +:= i - 1
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FI;
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i +:= 1
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OD
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END
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