\ Sieve benchmark              20oct87re ›                                         ›Onlyforth                                ›                                         ›: allot  ( u --)                         › dup sp@ here - $180 -  u>               › abort" no room" allot ;                 ›                                         ›&8192 Constant size                      ›Create flags   size allot                ›: do-prime  ( -- #primes )               › flags size 1 fill    0                  › size    0 DO flags I + c@               ›           IF  I 2* 3+ dup I +           ›             BEGIN  dup size <           ›             WHILE  0 over flags + c!    ›                    over +               ›             REPEAT  2drop 1+            ›           THEN                          ›        LOOP ;                           ›: benchmark   9 0 DO do-prime drop  LOOP › do-prime . ." Primzahlen" ;             ›: .primes   size 0 DO  flags I + c@      › IF  I 2* 3+ .  THEN ?cr                 › stop? IF  LEAVE  THEN  LOOP ;          ›