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copied!<p>In your sample snippet your use of <code>std::includes</code> is pointless since it will use <code>operator<</code> to compare your elements. Unless you are storing the <strong>same</strong> pointers in both your arrays the operation will not yield the result you are looking for.</p> <p>Comparing adresses is not the same thing as comparing the true content of your <em>c-style-strings</em>.</p> <hr> <p>You'll also have to supply <code>std::sort</code> with the neccessary comparator, preferrably <code>std::strcmp</code> (wrapped in a <em>functor</em>).</p> <p>It's currently suffering from the same problem as your use of <code>std::includes</code>, it's comparing addresses instead of the contents of your <em>c-style-strings</em>.</p> <hr> <p><em>This whole "problem" could have been avoided by using <code>std::string</code>s and <code>std::vector</code>s.</em></p> <hr> <p><strong>Example snippet</strong></p> <pre><code>#include <iostream> #include <algorithm> #include <cstring> typedef char gchar; gchar const * a1[5] = { "hello", "world", "stack", "overflow", "internet" }; gchar const * a2[] = { "world", "internet", "hello" }; </code></pre> <p>...</p> <pre><code>int main (int argc, char *argv[]) { auto Sorter = [](gchar const* lhs, gchar const* rhs) { return std::strcmp (lhs, rhs) < 0 ? true : false; }; std::sort (a1, a1 + 5, Sorter); std::sort (a2, a2 + 3, Sorter); if (std::includes (a1, a1 + 5, a2, a2 + 3, Sorter)) { std::cerr << "all elements in a2 was found in a1!\n"; } else { std::cerr << "all elements in a2 wasn't found in a1!\n"; } } </code></pre> <p><strong>output</strong></p> <pre><code>all elements in a2 was found in a1! </code></pre>

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