39 lines
742 B
Plaintext
39 lines
742 B
Plaintext
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BEGIN
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COMMENT
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BYTE magazine's CLASSIC SIEVE OF ERATOSTHENES;
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INTEGER o, limit, i, k, count, prime;
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BOOLEAN ARRAY flags[0:8190];
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limit := 8190;
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FOR o := 1 STEP 1 UNTIL 10 DO
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BEGIN
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FOR i := 0 STEP 1 UNTIL limit DO
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flags[i] := TRUE;
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count := 0;
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FOR i := 0 STEP 1 UNTIL limit DO
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BEGIN
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IF flags[i] THEN
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BEGIN
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prime := i + i + 3;
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IF prime < limit THEN
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BEGIN
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FOR k := (i + prime) STEP prime UNTIL limit DO
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flags[k] := FALSE;
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END;
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count := count + 1;
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END;
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END;
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END;
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text( 1, " PRIMES FOUND: ");
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write( 1, count );
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text( 1, "*N" );
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ioc(22);
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END
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FINISH
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