Hey! I want to ask a question that is what is the purpose of using cin.ignore() in C++? Like when or why to use it in code.

Answer 1

cin.ignore() is a predefined function which ignores/clears one or more characters from the input buffer.

Pre-requisites:
1. The cin treats a white space i.e  " "  ,   "\t"   , "\n" 
 as delimiter character.

2. When you read anything from the standard input device, keyboard here,
it firstly goes into the input buffer.
The input buffer is a location that holds all incoming information before it continues to the CPU for processing.

The Problem:
1. Suppose, you want to read a 'string' from the user.
char myname[10];

2. You somehow end up using cin, instead of cin.getline()
cin>>myname;

3. I type "ABC", and then press Enter key.
it takes up ABC and treats the following "\n"as delimeter.
As a result, "\n" is not read and it remains in the input buffer.

4. So here, cin.ignore() will ignore these unread characters that remained in the input buffer.

Answer 2

Thank you so much! 🙂
C.Gowthami