What is the data type of cin?

Question

For example

string name;
cin >> name; // Error
// You will get this error outside SL code playground

but when

Int num;
cin >> num; // ok

I am using Visual C++ compiler.

Thanks for helping me friends.

Answer 1

use this.

string name;

getline (cin, name);

/* any whitespaces with normal cin causes problems. */

edit

also, you will have problems with << operator.

Answer 2

Even the code in your question
Int num;
cin>>num;
cout>>num;
Will produce error.

It should be
int num;
cin>>num;
cout<<num;

Answer 3

cout is of type ostream
cin is of type istream

Answer 4

@anubhav
Well to be clear, cin and cout cant have a return type. They are not functions.

Answer 5

The class I/O libraries have good notes.

I will go over them, and see what I can use.

Answer 6

@kinshuk. you are correct. you knew what i meant though right

Answer 7

@anunhav. cool. you can also use this method to check for invalid input by preceeding cin with ! in the if statement

Answer 8

😉

Answer 9

so if we had a char array of sufficient size could the extraction operator work on cin?
edit: back to original question

double edit: i doubt it. as the operator probably isnt overloaded for cin but thought i would ask

Answer 10

@anubhav: sorry for the confusion. we are discussing what data type cin is. not its return type or lack thereof.

Answer 11

@anubhav pandey

Though cin cannot return anything, the operator >> does.

Its prototype:
friend istream& operator>>(istream& is, /*any thing to write*/);

Answer 12

@kinshuk: Well that answers that question then!

Answer 13

huh... it has a type??? google to the rescue. char

http://www.cplusplus.com/reference/iostream/cin/

i give this question 30 cookies

Answer 14

I was of the understanding that cout and cin are global variables contained in iostream. but I have been wrong before

Answer 15

@Manual: at the cin entry itself: http://www.cplusplus.com/reference/iostream/cin/

Then at istream class:
http://www.cplusplus.com/reference/istream/istream/

Answer 16

nope! I am moving away from console atm. Havent used cout or cin for a bit. Using streams a bit but for working with files

Answer 17

They are objects.
If not, why are we able to use:

cin.ignore();
getline(cin, string);

And getline has a prototype:
istream& getline( istream& is, string& str, char delim);

Answer 18

@jay
I think extraction operator is >> and not << acc to this:
https://msdn.microsoft.com/en-us/library/1z2f6c2k.aspx

And >> is default for cin, isn't it?

And I dont think cin<<var; is valid at all...
I mean, can you write data to a file opened in read only mode?

Eg -

ifstream fin;
fin.open("a.txt");
fin<<"Hello";
//I dont think its possible...

Answer 19

@Manual
cin and cout are global objects of the type i/o stream that have overloaded the >> and << operators with a function.

Answer 20

Oh okay.