Python: Composition of operations

Let's look at an example:

``````print(2 * 4 * 5 * 10)
``````

The operations can be combined with each other to calculate increasingly complex compound expressions. To give you an idea of how calculations are done inside the interpreter, let's look at an example: `2 * 4 * 5 * 10`.

1. First, we calculate `2 * 4` and get the expression `8 * 5 * 10`
2. Then `8 * 5`. The result is `40 * 10`
3. Then, we get the last multiplication, which gives us `400`

Operations may contain different operators, which raises the question of their priority.

Instructions

Write a program that calculates and prints the value of this expression:

``````8 / 2 + 5 - -3 / 2
``````

Don't calculate anything manually, your program should do all the calculations on its own.

The exercise doesn't pass checking. What to do? 😶

• 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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