Update README.md

Author: PetropoulakisPanagiotis

README.md

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 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
 # Algorithms
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+  <img width="450" height="300" src="https://www.geeksforgeeks.org/wp-content/uploads/Competitive-Programming-1.jpg">
+</p>
 
-<img align="center" width="450" height="300" src="https://www.geeksforgeeks.org/wp-content/uploads/Competitive-Programming-1.jpg">
 In this repository you can find some algorithms and data structures that I coded from scratch.
 
 ## Author