Epson FX Series User Manual page 207

Table 14-1. Variables
90 IF N>MIN THEN 70
100 NEXT J: PRINT
The J loop will Repeat four times (RE = 4). It has two subloops, each
of which depends on the value of N. Each time through the first loop
(lines 40 to 60), N increases by one-to the value of MAX. Each time
through the second loop (lines 70 to 90), N decreases by one-to the
value of MIN. For each value of N, the program calls subroutine 300,
and each time it is called, this subroutine adds more ones and zeros
into the array.
Enter the program lines for the subroutine by typing:
290 LPRINT CHR$(27)"2": END
FOR K=0 TO MAX-N
300
310
FOR L=l TO N
320
C=C+l: A(C)=X
330
NEXT L: X=1-X
340
NEXT K: PRINT N;: RETURN
190
SYMMETRY
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