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    <pre><code>if (i == poly.end()) { // if we reached the last term </code></pre> <p>This comment shows your error. For any given collection of items, <code>items.end()</code> returns the entry after the last item.</p> <p>For instance, say I have a 5-item std::vector:</p> <pre><code>[0] [1] [2] [3] [4] </code></pre> <p>Then begin() points to:</p> <pre><code>[0] [1] [2] [3] [4] /\ </code></pre> <p>And end() points to:</p> <pre><code>[0] [1] [2] [3] [4] [] /\ </code></pre> <p>Your for loop, it looks like:</p> <pre><code>for (i=poly.begin() ; i != poly.end(); i++ ) </code></pre> <p>Note that comparing <code>i</code> to <code>poly.end()</code> happens before iter is used. As soon as <code>i == poly.end()</code>, you're done. </p> <p>Your code inside of <code>if (i == poly.end()) {</code> will never be executed because this can never be true.</p> <p>You can test for the end using the following:</p> <pre><code>// get access to the advance function #include &lt;iterator&gt; .... std::list&lt;term&gt;::iterator endCheckIter = i; std::advance(endCheckIter, 1); if (endCheckIter == poly.end()) { ... } </code></pre> <p>But a simpler way might be:</p> <pre><code>std::list&lt;term&gt;::iterator endCheckIter = i; ++endCheckIter; if (endCheckIter == poly.end()) { ... } </code></pre> <p>Edit: I'm not sure why you're getting garbage. Add in your missing braces and handle the non-end case, and everything works here:</p> <pre><code>void print(char var) { list&lt;term&gt;::iterator endCheckIter; for (i=poly.begin() ; i != poly.end(); i++ ) { // &lt;- MISSING BRACE //going through the entire list to retrieve the terms and print them endCheckIter = i; ++endCheckIter; cout &lt;&lt; i-&gt;coef &lt;&lt; var &lt;&lt; "^" &lt;&lt; i-&gt;pow; // &lt;- MISSING OUTPUT if (endCheckIter != poly.end()) { if (i-&gt;coef &gt; 0) cout &lt;&lt; " + "; else cout &lt;&lt; " - "; } } // &lt;- MISSING BRACE } </code></pre>
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    1. COso what condition would be good for the last term? I mean i tried poly.end() - 1 but it doesn't work!
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    2. CO@Vlad: I'll add a note.
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    3. COSo in my example what it would have to look like so endCheckIter will always be in front of i?
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