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Quadratic Equation Solver

Author: student of group IM-33 Bondar Yaroslav

This is a simple console application that solves quadratic equations of the form:

ax^2 + bx + c = 0

where a, b, and c are real numbers, and a ≠ 0.

Features

• Supports interactive mode (user enters coefficients manually).
• Supports file-based mode (coefficients are read from a file).
• Handles invalid input gracefully.
• Provides meaningful error messages.

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Installation and Usage

1. Running in Interactive Mode

If no arguments are provided, the program runs in interactive mode.
Run the program and input coefficients when prompted:

python main.py

Example:

$ python main.py
a = 2
b = 4
c = 2
Equation is: (2.0) x^2 + (4.0) x + (2.0) = 0
There are 1 roots
x1 = -1.0

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2. Running in File-Based Mode

Provide the path to a file containing three numbers (a b c) separated by spaces:

python main.py coefficients.txt

File format example (coefficients.txt):

1 0 0

(Note: The file must end with a newline character.)

Example Output:

$ python main.py coefficients.txt
Equation is: (1.0) x^2 + (0.0) x + (0.0) = 0
There are 1 roots
x1 = 0.0

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Error Handling

The program detects and handles the following errors:

• Invalid input in interactive mode:

  a = invalid
  Error. Expected a valid real number, got 'invalid' instead
  

• File does not exist:

  $ python main.py non_existing.txt
  file non_existing.txt does not exist
  

• Invalid file format:

  $ python main.py wrong_format.txt
  invalid file format
  

• a cannot be 0 (not a quadratic equation):

  $ python main.py zero_a.txt
  Error. a cannot be 0
  

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Revert Commit

A revert commit was made as part of this assignment.
You can check the commit history to find the revert operation.

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License

This project is open-source and free to use.