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    <p>Several things jump out:</p> <ol> <li><p>In Java (and most other languages syntactically derived from B), the <em>logical</em> AND operator is <code>&amp;&amp;</code>, not <code>&amp;</code> (<code>&amp;</code> is a mathematical operator, doing a bitwise boolean OR).</p> <p>So</p> <pre><code>if (P1 == 1 &amp;&amp; P2 == 1) // ^^---- &amp;&amp;, not &amp; </code></pre></li> <li><p>In Java, variables have block scope. That means that a variable declared within a block is only available within that block (and any blocks it contains), not <em>outside</em> that block. So the <code>P2</code> you're defining inside the loop here:</p> <pre><code>do { System.out.println("Player 2, choose 1 for rock, 2 for paper, or 3 for scissors."); int P2 = input.nextInt(); // ^----------------------------- here } while (/*...*/); </code></pre> <p>...will only be available <em>within</em> the loop, not later after the loop. You need to declare that variable outside the loop. (And similarly for <code>P1</code>, of course.) In this case, the best place is the top of the function:</p> <pre><code>int P1, P2; </code></pre></li> <li><p>In any logical condition (including the condition of a <code>while</code>), to combine multiple criteria, you use logical operators <code>&amp;&amp;</code> ("and") and <code>||</code> ("or"), not semicolons (<code>;</code>). So for instance:</p> <pre><code>do { System.out.println("Player 2, choose 1 for rock, 2 for paper, or 3 for scissors."); P2 = input.nextInt(); } while (P2 != 1 &amp;&amp; P2 != 2 &amp;&amp; P2 != 3); // ^^---------^^---- "If P2 is not 1 AND P2 is not 2 AND P2 is not 3" </code></pre></li> <li><p>You have three different tests to see if it's a tie, and just generally you're doing a lot of retesting of the same conditions (lots of <code>P1 == 1</code>, <code>P2 == 2</code>, etc.). You can test for a tie simply by checking if <code>P1 == P2</code>, and you can reduce the number of condition checks markedly by using <code>else</code>, for instance:</p> <pre><code>if (P1 == P2) { System.out.println("It's a tie!"); } else if (P1 == 1) { if (P2 == 2) { System.out.println("Player 2 wins!"); } else { System.out.println("Player 1 wins!"); } } else if (P1 == 2) { if (P2 == 1) { System.out.println("Player 1 wins!"); } else { System.out.println("Player 2 wins!"); } } else { // P1 == 3 if (P2 == 1) { System.out.println("Player 2 wins!"); } else { System.out.println("Player 1 wins"); } } </code></pre></li> <li><p><em>(More advanced)</em> Look into <code>enum</code>s. In my reworking your logic, I simply trusted that your logic was correct, because I have no idea what <code>1</code>, <code>2</code>, or <code>3</code> are when looking at the code. (Obviously higher up I could look at the message you output.) Using an <code>enum</code> would make the code a lot clearer. (<code>if (P2 == RPS.Paper)</code>)</p></li> </ol> <p>I suggest working through some guided Java tutorials. Oracle <a href="http://docs.oracle.com/javase/tutorial/" rel="nofollow">has several</a>.</p>
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    1. UST.J. Crowder
    1. UST.J. Crowder
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    1. COMy bad. Thanks so much. So, how do I call on P1 and P2 in the while statement since it is in the do loop?
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    2. CO@ZeroConnor: What do you mean by "call on"?
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