Question

Which function is used to check whether a character is a number?

(a) isalpha()

(b) isalnum()

(c) isdigit()

(d) isblank()

I had been asked this question in an international level competition.

Enquiry is from Character Classification topic in section Types, Pointers, Arrays & Structures in C++ of C++

Answer 1

Right choice is (c) isdigit()

Explanation: Character classification provides isdigit() function to check whether a character in C++ is number or not.