Atari XL User Manual

CHAPTER 5
PROGRAM CONTROL
In the last chapter we defined a program as a-
numbered list of instructions to the computer,
which are obeyed in order from beginning to end.
In this chapter we will find out how to write
programs in which some instructions are executed
more than once. This makes programs more
efficient, as instructions which must be repeated
need to be written only once. We will also discover
that the computer can make decisions.
REPETITION
A section of program can be repeated many times
using the instructions FOR and NEXT. Try this
example:
10 FOR COUNT = 1 TO 10
20 PRINT COUNT
30 NEXT COUNT
which prints the numbers from 1 to 10 on the
screen. The section of program between the FO R
and the NEXT commands is repeated for each
value of COUNT, and COUNT is automatically
increased by one every time the NEXT command is
met in a loop. .
The variable in a FO R ... NE XT loop need not be
increased by 1; any increase or decrease can be
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Atari XL Specifications

General

Brand	Atari
Model	XL
Category	Desktop
Language	English