Hackerrank File I/O and Exception Handling

Question 1

Which built-in function is used to open a file in Python?

Accepted Answer

open()

Answer

The built-in `open()` function is used to open files in Python, returning a file object.

Question 2

What mode string opens a file for writing, creating it if it doesn't exist and truncating it if it does?

Accepted Answer

'w'

Answer

'w' opens a file for writing, creates it if missing, and truncates existing content to zero length.

Question 3

What is the preferred Python idiom for opening a file to ensure it is properly closed afterward?

Accepted Answer

with statement

Answer

The `with` statement uses the context manager protocol to automatically call `close()` when the block exits, even on exceptions.

Question 4

Which file method reads all remaining lines of a file and returns them as a list of strings?

Accepted Answer

readlines()

Answer

`readlines()` reads from the current position to EOF and returns a list where each element is one line including the newline character.

Question 5

What does the 'b' flag signify when added to a file mode (e.g., 'rb' or 'wb')?

Accepted Answer

Binary mode

Answer

The 'b' flag opens the file in binary mode, reading/writing raw bytes instead of decoded text strings.

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