In this tutorial, I will expand a card with AnimatedContainer to make it look better.


Writing Dart/Flutter articles is a great way to become a better software engineer and is often seen as a skill for senior developers. Writing articles it’s important because you are contributing to the community by sharing your learnings with other developers. Also, you can revisit the article whenever you want.

Given a non-empty array of integers, every element appears twice except for one. Find that single one.

For example, the peculiarity of this array [4, 3, 2, 4, 1, 3, 2] is that all numbers contained within it are duplicates except one. In this particular case, the non-duplicate number is 1

First solution

A possible solution is to use a hashmap and keep the occurrences of each number present…

Davide Agostini

Mobile Software Engineer (Android/Flutter💙) who loves create interesting mobile apps with an eye to UI.

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