Ch 9_2. Beyond the basic PERFORM (II)

PERFORM times

Sum of odd numbers: 1+3+5+ ... +49 
     MOVE 1 TO NUM
     MOVE 0 To SUM

     PERFORM 25 TIMES 
        ADD NUM TO SUM
        ADD 2 TO NUM
     END-PEFORM

     DISPLAY SUM
Another Way 
     MOVE 1 TO NUM
     MOVE 0 To SUM

     PERFORM UNTIL NUM > 50 
        ADD NUM TO SUM
        ADD 2 TO NUM
     END-PEFORM

     DISPLAY SUM

PERFORM varying FROM BY

     MOVE 0 To SUM

     PERFORM varying NUM from 1 by 2 until NUM > 50
        ADD NUM TO SUM
     END-PERFORM