\ Copyright BYTE magazine \ (* The Sieve of Eratosthanes, compiled *) / DECIMAL 8192 CONSTANT size size string flags : DO-PRIME flags size 1 FILL 0 size 0 DO flags I + C@ IF I DUP + 3 + DUP I + BEGIN DUP size < WHILE 0 OVER flags + C! OVER + REPEAT DROP DROP 1+ THEN LOOP ; : PRIMES ." Going to do 25 iterations." 0 25 0 DO DROP DO-PRIME LOOP CR . ." primes found," ; CR ." Enter PRIMES to test." \ (* End of Information *) CR PRIMES CR