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<h1>Lecture for January 30</h1>
<h2>Random Number Generator</h2>
<p>One of the ways you can do a random number generator is through this method:</p>
<p>Import a class called random </p>
<pre><code class="language-java">import java.util.Random;</code></pre>
<p>Then you need to create a <code>Random</code> object</p>
<pre><code class="language-java">Random rand = new Random();</code></pre>
<p>After this you can call the <code>nextInt()</code> method to get a random number between 0 and $2^{32}$</p>
<pre><code class="language-java">int randInt = rand.nextInt();</code></pre>
<p>If you don't want a random number between 0 and $2^{32}$ but instead to another maximum value, then you can call the <code>nextInt</code> method inserting the max integer as a parameter.</p>
<p>Random Integer from 0-10 (not including 10)</p>
<pre><code class="language-java">int randInt2 = rand.nextInt(10);</code></pre>
<h2>Output</h2>
<p>We have already encountered <code>System.out.println</code> and <code>System.out.print</code> but let us go over the differences again.</p>
<p><code>System.out.println()</code> prints the contents inside the parenthesis and appends a newline character afterwards so that the next output is on a new line</p>
<p><code>System.out.print()</code> prints the contents inside the parenthesis and does not output a newline character</p>
<h3>Formatting Output</h3>
<p>If you want more control on how your output is displayed, it is recommended that you use <code>System.out.printf</code> to format your output</p>
<p>First, you need to specify your type using the % instruction</p>
<ul>
<li>d for integer</li>
<li>f for decimal</li>
</ul>
<p>Example:</p>
<pre><code class="language-java">int sum = 50;
System.out.printf("Total = %d", sum);</code></pre>
<p>This outputs </p>
<pre><code class="language-reS">Total = 50</code></pre>
<p>Notice here that there is no concatenation required like the previous two methods, instead you insert the variables as parameters</p>
<p>Let us deconstruct the % instruction</p>
<p>% <strong> </strong> . <strong> </strong></p>
<p>The first underline is the + - 0 space (sometimes we want to pad the money with zeros)</p>
<p>The second underline is the width of the text</p>
<p>The third underline is the number of decimal places</p>
<p>The the final underline is the specifier <code>f</code> for decimal and <code>d</code> for integer</p>
<p><u>Example</u></p>
<pre><code class="language-java">double amount = 0.5;
System.out.printf("Total Due: %0.2f")</code></pre>
<p>This outputs</p>
<pre><code class="language-reStructuredText">Total Due: 0.50</code></pre>
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