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    copied!<pre><code>ave = sum/array.size(); </code></pre> <p>That will do integer division. The average is very likely going to be a floating point value, so you need to cast first:</p> <pre><code>float ave = static_cast&lt;float&gt;(sum) / array.size(); </code></pre> <p>To do the other averages, you'll want to sum up only the positive and negative values, respectively, and then divide by the number of positive and negative numbers, respectively.</p> <p>Just to show it can be done:</p> <pre><code>void averages(const std::vector&lt;int&gt;&amp; vec, double&amp; overall_average, double&amp; positive_average, double&amp; negative_average) { std::tuple&lt;int, int, int, int, int, int&gt; sums_and_counts = std::accumulate(vec.begin(), vec.end(), std::make_tuple(0, 0, 0, 0, 0, 0), [](std::tuple&lt;int, int, int, int, int, int&gt; t, int i) { std::get&lt;0&gt;(t) += i; std::get&lt;1&gt;(t) += 1; if (i &lt; 0) { std::get&lt;2&gt;(t) += i; std::get&lt;3&gt;(t) += 1; } if (i &gt; 0) { std::get&lt;4&gt;(t) += i; std::get&lt;5&gt;(t) += 1; } return t; }); overall_average = positive_average = negative_average = 0.0; if (std::get&lt;1&gt;(sums_and_counts)) { overall_average = static_cast&lt;double&gt;(std::get&lt;0&gt;(sums_and_counts)) / std::get&lt;1&gt;(sums_and_counts); } if (std::get&lt;3&gt;(sums_and_counts)) { negative_average = static_cast&lt;double&gt;(std::get&lt;2&gt;(sums_and_counts)) / std::get&lt;3&gt;(sums_and_counts); } if (std::get&lt;5&gt;(sums_and_counts)) { positive_average = static_cast&lt;double&gt;(std::get&lt;4&gt;(sums_and_counts)) / std::get&lt;5&gt;(sums_and_counts); } } </code></pre>
 

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