Python script takes input of four elements and outputs a valid 4 × 4 Sudoku grid in O(n) time, but only when given non-repeating elements

Question

Introduction

I've found a clever and fun thing to do after solving a n² × n² sudoku puzzle. I can take a grid as such as this one and hard-code its indices as constraints to output other 4 × 4 latin squares in poly-time

Now, I took each successive row and hardcoded as indices with successive print statements.

Indices constraints

0123
3210
1032
2301

Working Code

print('enter with [1,2,3...] brackets')
text = input()[1:-1].split(',')
print(text[0], text[1], text[2], text[3])
print(text[3], text[2], text[1], text[0])
print(text[1], text[0], text[3], text[2])
print(text[2], text[3], text[0], text[1])

Question

Being a novice at python I'm asking is there a better way of hardcoding the Sudoku's pattern with fewer lines of code?

Because it would be daunting to have to write larger constraints for larger latin squares.

I would appreciate it to keep it O(n) time because I have a desire to input integers besides just elements 1-4. But, 100-104 and so on..

Answer 1

• Use json to simplify your input handling.
• You can use str.format to simplify all the prints.
• You don't handle incorrect data well. What if I enter 3 or 5 numbers?
• Your code doesn't run in \$O(n)\$ time, it runs in \$O(n^2)\$ time. I recommend that you ignore \$O\$ and just get working code if you're a novice. After you get it working make it readable. Finally here you should time your code to see if you need to then optimize it.
• Use functions, they make your code easier to use.

import json


def handle_input(input_):
    try:
        data = json.loads(input_)
    except ValueError:
        raise ValueError('Invalid format.')

    if len(data) != 4:
        raise ValueError(f'Incorrect amount of numbers, got {len(data)} not 4.')
    return data


def main():
    print('Enter four numbers in brackets. E.g. [1, 2, 3, 4]')
    data = handle_input(input())
    print(
        '{0} {1} {2} {3}\n'
        '{3} {2} {1} {0}\n'
        '{1} {0} {3} {2}\n'
        '{2} {3} {0} {1}\n'
        .format(*data)
    )


if __name__ == '__main__':
    main()