simple09.html

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layout: base.html
title: Simple HTML - Comparing things
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		<h1>Comparing things</h1>
<p>You can make a computer compare pieces of
	information and then do different things according to
	the results. To do this you use the commands <code class="command">IF</code> and
	<code class="command">THEN</code>. You can find out how <code class="command">IF</code> and <code class="command">THEN</code> work in the
	program below.</p>
<pre>
NEW
10 CLS
20 PRINT "TYPE IN TWO NUMBERS"
30 INPUT A
40 INPUT Z
50 IF A=Z THEN PRINT "EQUAL"
60 IF A&lt;>Z THEN PRINT "NOT EQUAL"
RUN
</pre>

<p>
	In this program the <code class="command">IF</code> and <code class="command">THEN</code> commands
	make the computer compare the numbers
	stored in the variables A and Z. If the
	numbers are the same the computer displays
	the message "EQUAL". If the numbers are
	different, the message is "NOT EQUAL".
</p>

<aside>
	The <code>=</code> symbol compares the numbers to see if they are the same. The <code>&lt;&gt;</code> symbol compare the numbers to see if they are different.
</aside>

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	<article>
		<h2>Comparing words</h2>
		<p>
You can also use <code class="command">IF</code> and <code class="command">THEN</code> to
make the computer compare words.
Try running the program below.
The <code class="command">IF</code> and <code class="command">THEN</code> commands make
the computer compare the
names stored in <code>S$</code> and
<code>N$</code>, to see if they are the
same or not.
		</p>
<pre>
NEW
10 CLS
20 S$="SLIMY SID"
30 PRINT "WHAT'S YOUR NAME?"
40 INPUT N$
50 IF N$<>S$ THEN PRINT "I CAN'T STAND MONSTERS CALLED "; N$
60 IF N$=S$ THEN PRINT "HELLO ";S$;" NICE TO MEET YOU"
RUN
</pre>
</article>
<article>
	<h2>Age program</h2>

<p>
When you type in this program, put your own age in line 20. Then let a friend run the
program. The computer will work out whether your friend is older, younger or the same age as you.
</p>

<pre>
NEW
10 CLS
20 A=11
30 PRINT "I AM";A;" YEARS OLD"
40 PRINT "HOW OLD ARE YOU?"
50 INPUT B
60 IF A=B THEN PRINT "WE'RE THE SAME AGE!"
70 IF A>B THEN PRINT "I'M OLDER THAN YOU"
80 IF A&lt;B THEN PRINT "I'M YOUNGER THAN YOU"
RUN
</pre>
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