Fairly Beginner Programming Excercises

I have been trying to teach programming to one of my friend and occasionally I search online for fun projects which I can give it to him as programming exercises. I will try to document the ones I gave him with notes on what I intended him to learn from the exercise:

******* Loops and Constructs ********

1) Project 1: Print a pyramid. Read (in a loop of course) a number, n, and print a pyramid that has that size. The example below shows what would be printed for n=4.


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2) Project 2: Printing prime numbers: This is more sort of a classic programming problem and involves knowledge of basic programming constructs such as conditions, looping etc.

3) Project 3: Printing the first n fibonacci numbers. This is again a classic programming problem and involves knowledge of basic programming constructs.


******* Arrays ***********

1) Project 1: Finding missing elements in a array. So basically a array is provided that has certain missing elements like numbers between 1 - 99. The task here is to find those missing numbers from the array. This project basically requires knowledge of arrays and array traversal.

2) Project 3: Sorting a number array: This is again a classic programming problem and can be done in various ways. Knowledge gained here is again arrays.

******* Hash *********

1) Project 1: Parse a file and display words that occur more than n times. Not a requirement that you use a hash here but ideally you would.

2) Project 2: