Link ~> https://go-left.com/blog/programming/100-little-programming-exercises/

The exercises are grouped in three categories for people who want to learn to write software and for experienced developers who are learning a new language. The exercises focus on learning how to use control structures (if/then/else/switch/for/repeat/while) and data structures (variable/list/map/stack/dictionary/pointer).

They do not require a complex user interface although nobody is stopping you from writing one. You learn something there as well. My personal experience is that when learning a new language designing the user interface can get in the way and chew up a lot of time – your mileage may vary

Beginner
These exercises don’t require a complex algorithm and therefore focus on the task of writing the program, getting used to the language and the development environment. The solution should in general be far less than 100 lines of code. They are good exercises for beginners and experienced developers trying to learn a new language. To an experienced developer the approach should be immediately obvious.

Intermediate
The intermediate exercises don’t require a complex algorithm as well but they are more advanced in terms of data structures and data processing. Their solution should not be immediately obvious or there are multiple ways of solving the problem. These problems are for people who are learning to write software and who mastered the beginner problems. They are also suited for experienced developers looking for a small challenge.

Advanced
These exercises are algorithmically challenging and may be computationally complex. Their solutions should not be immediately obvious and require some research.

Here is the list of exercises

Beginner
A.1 Factorial
A.2 Currency Calculator
A.3 Roll the Dice
A.4 Reverse the Input
A.5 Count Words and Lines
A.6 Min and Max
Intermediate
B.1 Calculator
B.2 Bubblesort
Advanced
C.1 Towers of Hanoi
Simple Problems


A.1 Factorial

Write a program which takes a single argument, computes the factorial and prints the value on the screen.

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$ factorial 5
5! = 120
Ext 1: Change the program so that it computes the factorial iteratively and recursively.

Ext 2: Change the program so that it is interactive instead of terminating after each computation and that it uses a table of previous values to improve the performance.

A.2 Currency Calculator

Write a program which takes a decimal value and two ISO 4217 currency codes and computes the value of the other currency given a fixed conversion rate. If one of the currency codes is not known the program should print an error. When run without any arguments the program should print some usage information including a list of all known currency codes for which it has conversion rates.

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$ convert 112.34 USD EUR
112.34 USD = 84.50 EUR (Conversion rate: 1 USD = 0.7522 EUR)

A.3 Roll the Dice

Write a program which simulates one or more dice with values from 1 to 6. The program takes a single argument which is the number of dice. The output should contain the values of the dice and the probability for this combination to occur. The probability is expressed as a decimal value between 0 and 1 with three decimal points.

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$ roll-the-dice 3
Rolling 3 dice ...
4 2 8 (Probability: 0.473)
Ext 1: Extend the program so that it can roll dice with any number of sides greater than 1.

A.4 Reverse the Input

Write a program which reads a number of strings from standard input and prints them in reverse order on the screen. The input sequence is terminated with the string END.

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$ reverse-strings
one
two
three
END
-> three
-> two
-> one

A.5 Count Words and Lines

Write a program which reads the contents of a file and which counts the number of words and lines in that file.

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$ count-words-and-lines file.txt
file.txt contains 525 words in 23 lines

A.6 Min and Max

Write a program which accepts numbers as arguments and which determines the lowest and highest number.

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$ min-max 1 10 99 5 19 -23 17
Read 7 numbers
Min value: -23
Max value: 99
Intermediate Problems


B.1 Calculator

Write a calculator which evaluates expressions with decimal numbers and the operators +, -, *, / and prints the result on the screen.

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$ calc 7 + 3 * 5
7 + 3 * 5 = 22

B.2 Bubblesort

Write a program which reads strings from standard input and sorts them using the Bubblesort algorithm. Determine the execution time with 10, 1000, 1000000 entries using time.

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$ time cat 1000-strings | bubblesort
Difficult Problems


C.1 Goat-Wolf-Salad

A goat, a wolf and a salad are on one side of a river and you need to get them to the other side using your boat. You can carry one item in your boat to the other side at any given time. However, when the goat and the wolf are left alone the wolf will eat the goat. If the goat and the salad are left alone the goat will eat the salad. As long as you are with them nothing will happen, i.e. the wolf won’t eat the goat and the goat won’t eat the salad.

Write a program which determines algorithmically an order in which you carry them all to the other side.

@OP Nice one..

In addition to the exercises: www.ling.gu.se/~lager/python_exercises.html