C LOGICAL*1 FLAGS(255) INTEGER COUNT, PRIME, SIZE C SIZE=255 C START=SECNDS(0.) C DO 1000 ITER=1,10 COUNT=0 I=0 DO 100 I=1,SIZE 100 FLAGS(I)=.TRUE. C DO 200 I=1,SIZE IF(.NOT.FLAGS(I)) GOTO 200 PRIME=I+I+1 COUNT=COUNT+1 K=I+PRIME DO 150 J=K,SIZE,PRIME 150 FLAGS(J)=.FALSE. 200 CONTINUE 1000 CONTINUE C TIME=SECNDS(START) C TYPE *,COUNT,' PRIMES FOUND ',ITER-1,' TIMES IN ',TIME,' SECOND' C STOP END