C++ Taskbook Level 8.3

You are given a text file. It contains text and numbers. Square each of these numbers and write the result back to the same file.

Given a folder with files. Delete all files with a given extension from this folder.

Given an array. Write the elements of this array to a file so that each element is written on a new line.

Make a function that will return an array filled with N random numbers from a given range such that the numbers do not repeat.