Sharp MZ-800 - Page 71

FOR ~ NEXT
Format
Abbreviated Format
FOR <control variable> = <initial value> TO <final value>
IBTEE, <increment >]
NEXT <control variable >
Explanation
Example
F.~N.
The FOR ~ NEXT statements repeat the instructions between the FOR and NEXT
variables the specified number of times.
10 A=0
20 FOR N=0O TO 10 STEP 2
30 A=A+1
40 PRINT “N="";N,
50 PRINT “A=""A
60 NEXT N
(1) In the program above, 0 is assigned to N as the initial value.
(2) Next, lines 20 through 50 are executed and the values of variables A and N dis-
played.
(3) In line 60, the value of N is increased by 2, after which the BASIC interpreter
checks to see whether N is greater than 10, the final value. If not, lines follow-
ing line 20 are repeated.
When the value of N exceeds 10, the program leaves the loop and the subsequent
instructions (on lines following line 60) are executed. The program above repeats
the loop 6 times.
If STEP <increment> is omitted from the statement specification, the value of
<control variable> is increased by | each time the loop is repeated. In the pro-
gram above, omitting STEP2 would result in 11 repetitions of the loop.
FOR Nag TO 10 STEP 2
Initial value Final value — Increment
of N for N for N
NEXT N
FOR ~ NEXT loops may be nested within other FOR ~ NEXT loops. When doing
this, inner loops must be completely enclosed within outer ones, and not overlap.
Also, separate control variables must be used for each loop.
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