<h2 id="heading-url">URL</h2>
<p><a target="_blank" href="https://leetcode.com/problems/rank-transform-of-an-array/description/?envType=daily-question&amp;envId=2024-10-02">Rank Transform of an Array - LeetCode</a></p>
<h2 id="heading-code">Code</h2>
<p><a target="_blank" href="https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/challenge/202410/rank_transform_of_an_array/main.fsx">https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/challenge/202410/rank_transform_of_an_array/main.fsx</a></p>
<pre><code class="lang-fsharp"><span class="hljs-keyword">let</span> arrayRankTransform (arr: int list) : int list =
    <span class="hljs-keyword">let</span> m =
        arr
        |&gt; List.countBy id
        |&gt; List.map fst
        |&gt; List.sort
        |&gt; List.indexed
        |&gt; List.fold (<span class="hljs-keyword">fun</span> acc (i, n) -&gt; Map.add n (i + <span class="hljs-number">1</span>) acc) Map.empty

    arr |&gt; List.map (<span class="hljs-keyword">fun</span> n -&gt; Map.find n m)
</code></pre>


## URL

[Rank Transform of an Array - LeetCode](https://leetcode.com/problems/rank-transform-of-an-array/description/?envType=daily-question&envId=2024-10-02)

## Code

[https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/challenge/202410/rank\_transform\_of\_an\_array/main.fsx](https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/challenge/202410/rank_transform_of_an_array/main.fsx)

```fsharp
let arrayRankTransform (arr: int list) : int list =
    let m =
        arr
        |> List.countBy id
        |> List.map fst
        |> List.sort
        |> List.indexed
        |> List.fold (fun acc (i, n) -> Map.add n (i + 1) acc) Map.empty

    arr |> List.map (fun n -> Map.find n m)
```

LeetCode 1331. Rank Transform of an Array in F#

URL

Code