difference between input using ignore and so on

Question

I wanted to clear some doubt regarding the function

cin.ignore(1,'\n');

code:

char x[80];      
cin>>x;       
cin.ignore(1,'\n');

If user input the word: paul Smith
does the program looks for the first space in the word and ignores/delete the rest of the characters?
Hence the program takes paul only and discards Smith?
Am I right?
I'm getting confused! Please explain in really simple words because I cannot understand the explanation on google regarding this issue.

Useful information to study: http://en.cppreference.com/w/cpp/io — πάντα ῥεῖ, Sep 25 '15 at 21:19
possible duplicate of [When and why do I need to use cin.ignore() in C++?](http://stackoverflow.com/questions/25475384/when-and-why-do-i-need-to-use-cin-ignore-in-c) — NendoTaka, Sep 25 '15 at 21:21

score 0 · Accepted Answer · answered Sep 25 '15 at 21:19

cin.ignore(1,'\n');

is not very useful. It will ignore only one character.

cin.ignore(100,'\n');

will ignore up to 100 characters but will stop after it encounters a '\n'.

In your case,

cin>>x;

will read paul into x. The line

cin.ignore(1,'\n');

will consume the space after paul. Hence, Smith will be left on the input stream.

Hence the program takes paul only and discards Smith?

No. I hope that is clear from the above.

score 0 · Answer 2 · answered Sep 25 '15 at 21:22

cin >> x;

Since x is a string or char array, this reads one word (everything up to the first whitespace character) from the input, and stores it in x.

cin.ignore(1, '\n');

reads and ignores one character from the input. It won't read the whole rest of the line. More generally:

cin.ignore(n, delim);

reads and ignores characters until it has either read n characters or reached a character equal to delim. If you want to ignore until the end of the line, no matter how many characters that is, do:

cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');

difference between input using ignore and so on

2 Answers2