Python Coding challenge - Day 719| What is the output of the following Python Code?

 

Code Explanation:

1) from functools import lru_cache

Imports the lru_cache decorator from Python’s functools module.

lru_cache (Least Recently Used cache) is used to memoize function results:

If a function is called with the same arguments again, it returns the cached result instead of recalculating.

2) @lru_cache(maxsize=None)

Decorates the function square.

maxsize=None means:

There’s no limit on how many results can be cached.

All calls with unique arguments are remembered.

3) def square(x):

Defines the function square that takes an argument x.

4) print("calc", x)

This line prints "calc", x every time the function actually computes something.

If the result is returned from cache, this line will not run.

5) return x * x

Computes the square of x and returns it.

6) print(square(3))

First call:

Since 3 is not in the cache, square(3) runs fully.

Prints "calc 3".

Returns 9.

So print(...) prints 9.

7) print(square(3))

Second call:

Now 3 is already cached.

The function body does not execute again (no "calc 3" this time).

Cached value 9 is returned instantly.

print(...) prints 9.

Final Output

calc 3

9

9

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