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    <p>In standard C++ you can default-initialize just about anything, including that array:</p> <pre><code>bool* boolArray = new bool[size](); // Zero-initialized </code></pre> <p>Complete program that also checks the result, and deallocates the array:</p> <pre><code>bool foo( int size ) { bool* boolArray = new bool[size](); // Zero-initialized // Check that it is indeed zero-initialized: for( int i = 0; i &lt; size; ++i ) { if( boolArray[i] ) { delete[] boolArray; return false; } } delete[] boolArray; return true; } #include &lt;iostream&gt; int main() { using namespace std; cout &lt;&lt; (foo( 42 )? "OK" : "Ungood compiler") &lt;&lt; endl; } </code></pre> <p>Whether your compiler will accept or even do the Right Thing is another matter.</p> <p>So, in practice, <em>if</em> you feel an irresistible urge to use a raw array, then perhaps better use <code>std::fill</code> or some such, or even a raw loop.</p> <p>But note the repeated <code>delete[]</code>-expressions. Such redundant code is very easy to get wrong: it's Evil&trade;. And there's much else that can go wrong with use of raw arrays, so as a novice, just Say No&trade; to raw arrays and raw pointers and such.</p> <p>Instead, use standard library containers, which manage allocation, initialization, copying and deallocation for you &ndash; correctly. There is a little problem with that, though, namely a premature optimization in <code>std::vector&lt;bool&gt;</code>, which otherwise would be the natural choice. Essentially <code>std::vector&lt;bool&gt;</code> uses just one bit per value, so that it can't hand out references to <code>bool</code> elements, but instead hands out proxy objects&hellip;</p> <p>So, for <code>bool</code> elements, use e.g. a <code>std::bitset</code> (when the size is known at compile time), or e.g. a <code>std::deque</code>, as follows:</p> <pre><code>#include &lt;deque&gt; bool foo( int size ) { std::deque&lt;bool&gt; boolArray( size ); // Zero-initialized for( int i = 0; i &lt; size; ++i ) { if( boolArray[i] ) { return false; } } return true; } #include &lt;iostream&gt; int main() { using namespace std; cout &lt;&lt; (foo( 42 )? "OK" : "Ungood compiler") &lt;&lt; endl; } </code></pre> <p>Cheers &amp; hth.,</p>
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