Python Coding challenge - Day 290| What is the output of the following Python Code?

 

Explanation:

Function Definition with a Default Argument:

def func(x=[]):

The function func is defined with a default parameter x, which is initialized to an empty list [] if no argument is passed during the function call.

Important behavior: Default arguments are evaluated once when the function is defined, not each time the function is called. This means if you use a mutable default argument (like a list), it will persist across multiple function calls.

Appending to the List:

x.append(1)

Inside the function, the code x.append(1) adds the value 1 to the list x.

Since x is initialized to an empty list [], 1 will be appended to it on the first call.

Return the List:

return x

After appending 1, the list x is returned.

First Function Call:

print(func())

When func() is called the first time, the default list x is an empty list [].

1 is appended to this list, making it [1], and this list is returned and printed.

Second Function Call:

print(func())

When func() is called the second time, the same list is used (because of the default argument behavior).

The list from the previous call already contains [1].

1 is appended again, so the list becomes [1, 1], and this list is returned and printed.

Final Output:

[1]

[1, 1]