Python: Commutative operation
"An operation will not change if the operands are moved” is one of the basic laws of arithmetic, also called the commutative law. A binary operation is considered commutative if you get the same result even if you swap the operands. In this case, addition is a commutative operation: `3 + 2 = 2 + 3'.
But subtraction is not a commutative operation: `2 - 3 ≠ 3 - 2'. In programming, this law applies just like it does in arithmetic. Moreover, most of the operations we encounter in real life are not commutative. Here's the takeaway: always pay attention to the order of things you work with.
Write a program that calculates and displays sequentially (one value per line) the values of the following mathematical expressions: "3 to the power of 5" and "-8 divided by -4".
The exercise doesn't pass checking. What to do? 😶
If you've reached a deadlock it's time to ask your question in the «Discussions». How ask a question correctly:
- Be sure to attach the test output, without it it's almost impossible to figure out what went wrong, even if you show your code. It's complicated for developers to execute code in their heads, but having a mistake before their eyes most probably will be helpful.
In my environment the code works, but not here 🤨
Tests are designed so that they test the solution in different ways and against different data. Often the solution works with one kind of input data but doesn't work with others. Check the «Tests» tab to figure this out, you can find hints at the error output.
My code is different from the teacher's one 🤔
It's fine. 🙆 One task in programming can be solved in many different ways. If your code passed all tests, it complies with the task conditions.
In some rare cases, the solution may be adjusted to the tests, but this can be seen immediately.
I've read the lessons but nothing is clear 🙄
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Commutativity the property of an operation where changing the order of operands does not affect the result. For example, addition is a commutative operation: changing the order of the numbers we are adding doesn't change the result.