実行ボタンが見えない時
<blockquote>
The file in the editor is not runnable
</blockquote>
<img src="https://storage.googleapis.com/zenn-user-upload/fdc251d0c304-20230222.png" alt loading="lazy" class="md-img">
Sources Rootを設定すればOK
<img src="https://storage.googleapis.com/zenn-user-upload/7a26ec8a5eaf-20230222.png" alt loading="lazy" class="md-img"> 
Mark Directory as → Sources Root
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IntelliJ:実行ボタンが見えない時

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