<h2 id="heading-url">URL</h2>
<p><a href="https://leetcode.com/problems/max-number-of-k-sum-pairs/" class="autolinkedURL autolinkedURL-url" target="_blank">leetcode.com/problems/max-number-of-k-sum-p..</a></p>
<h2 id="heading-code">Code</h2>
<p><a href="https://github.com/syohex/dotnet-study/blob/master/fsharp/leetcode/problems/1679/main.fsx" class="autolinkedURL autolinkedURL-url" target="_blank">github.com/syohex/dotnet-study/blob/master/..</a></p>
<pre><code class="lang-fsharp">let maxOperations (nums: int list) (k: int) : int =
    let rec maxOperations' nums k m ret =
        match nums with
        | [] -&gt; ret
        | h :: t -&gt;
            let diff = k - h

            match Map.tryFind diff m with
            | Some (v) when v &gt;= 1 -&gt; maxOperations' t k (Map.add diff (v - 1) m) (ret + 1)
            | _ -&gt;
                match Map.tryFind h m with
                | None -&gt; maxOperations' t k (Map.add h 1 m) ret
                | Some (w) -&gt; maxOperations' t k (Map.add h (w + 1) m) ret

    maxOperations' nums k Map.empty 0
</code></pre>


## URL

https://leetcode.com/problems/max-number-of-k-sum-pairs/

## Code

https://github.com/syohex/dotnet-study/blob/master/fsharp/leetcode/problems/1679/main.fsx

```fsharp
let maxOperations (nums: int list) (k: int) : int =
    let rec maxOperations' nums k m ret =
        match nums with
        | [] -> ret
        | h :: t ->
            let diff = k - h

            match Map.tryFind diff m with
            | Some (v) when v >= 1 -> maxOperations' t k (Map.add diff (v - 1) m) (ret + 1)
            | _ ->
                match Map.tryFind h m with
                | None -> maxOperations' t k (Map.add h 1 m) ret
                | Some (w) -> maxOperations' t k (Map.add h (w + 1) m) ret

    maxOperations' nums k Map.empty 0
```


LeetCode 1679. Max Number of K-Sum Pairs in F#

URL

Code