how to remove duplicate elements from an array of arrays in PHP : <pre><code>"2017-08-31":["5948a0dd21146a43fdcfef5a","5948a0dd21146a43fdcfef5a"]
"2017-08-22":["5948a0dd21146a43fdcfef5a"]
"2017-08-09":["59461ceae6179b19403c6a19","59461ceae6179b19403c6a19"]
"2017-08-08":["59461ceae6179b19403c6a19","59461ceae6179b19403c6a19"]
</code></pre>

<p>I have an array like this, key is a date and multiple value associated with that date, but I need unique value with that key.how to do that ? 
I've tried with <strong>array_unique</strong> but no luck!</p>
