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 ### Using the C++ language for the Programming Marathon.
 * The purpose of this repository is to study the C++ Language in more detail to use it in the Programming Marathon.
 * This repository builds on topics covered in the Competitive Programming guide on the GeeksforGeeks website. Guide link https://www.geeksforgeeks.org/competitive-programming-a-complete-guide/
+
+#### The problems were taken from sites like:
+* Hackerrank, GeeksforGeeks and LeetCode.
+* Each resolution source code has a direct link to the problem description.