<h2 id="heading-url">URL</h2>
<p><a target="_blank" href="https://leetcode.com/problems/number-of-good-pairs/description/?envType=daily-question&amp;envId=2023-10-03">Number of Good Pairs - LeetCode</a></p>
<h2 id="heading-code">Code</h2>
<p><a target="_blank" href="https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/problems/1512/main.fsx">https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/problems/1512/main.fsx</a></p>
<pre><code class="lang-fsharp"><span class="hljs-keyword">let</span> numIdenticalPairs (nums: int list) : int =
    <span class="hljs-keyword">let</span> <span class="hljs-keyword">rec</span> numIdenticalPairs' nums acc =
        <span class="hljs-keyword">match</span> nums <span class="hljs-keyword">with</span>
        | [] -&gt; acc
        | h :: t -&gt;
            <span class="hljs-keyword">let</span> matched = List.filter ((=) h) t |&gt; List.length
            numIdenticalPairs' t (matched + acc)

    numIdenticalPairs' nums <span class="hljs-number">0</span>
</code></pre>


## URL

[Number of Good Pairs - LeetCode](https://leetcode.com/problems/number-of-good-pairs/description/?envType=daily-question&envId=2023-10-03)

## Code

[https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/problems/1512/main.fsx](https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/problems/1512/main.fsx)

```fsharp
let numIdenticalPairs (nums: int list) : int =
    let rec numIdenticalPairs' nums acc =
        match nums with
        | [] -> acc
        | h :: t ->
            let matched = List.filter ((=) h) t |> List.length
            numIdenticalPairs' t (matched + acc)

    numIdenticalPairs' nums 0
```

LeetCode 1512. Number of Good Pairs in F#

URL

Code