Question

Which of the following is correct about none() function in bitset?

(a) Returns true if any bits is set 1

(b) Returns true if all bits is set 0

(c) Returns true if the number of 1’s equal to the number of 0’s

(d) Returns true only if all bits are 1

I got this question during an interview.

This interesting question is from Bitset topic in division Class Hierarchies, Library & Containers of C++

Answer 1

Correct choice is (b) Returns true if all bits is set 0

Easiest explanation - <bitset> header provides the any() function which returns true if none of the bit is set to 1 in the bitset variable.