CODEWITHSUNDEEP
c++cin
pranay godha
pranay godha

Reputation: 655

cin doesn't take input as ENTER

char ch[4];  
char* ptr;  
ptr = ch;  
while(1)  
{  
  cin >> *ptr;  
if(*ptr == '\n')  
break;  
ptr++;  
}

Here I just wrote a bit of sample code where I am trying to get out of a while loop when user writes ENTER but it's not working. Please help me. Thank you in advance.

Upvotes: 0

Views: 764

Answers (4)

Abhishek Bagchi
Abhishek Bagchi

Reputation: 21

The extraction operator would skip leading white-spaces and stop execution on encountering any subsequent white-space. So, when you want to do something like this, use std::istream::get() or std::istream::getline().

Upvotes: 1

Tech Agent
Tech Agent

Reputation: 657

The following will read a line:

istream& getline (char* s, streamsize n );

Upvotes: 1

Randall Cook
Randall Cook

Reputation: 6776

You are reading input into the value of a character. That's what *ptr means. I think you want just plain ptr, which is a pointer to an array of characters, which is something that is meant to receive data. What you wrote is basically this:

char c;
cin >> c;

I don't think that's what you meant, nor would it work even if it were, since as Joachim Pileborg points out above, the >> operator skips whitespace like newlines. In general, it is always best to be very robust when it comes to reading input. Provide adequate space, and either use a variable that can grow automatically (like std::string) or tell the system how much space you have (like fgets()).

Upvotes: 1

Some programmer dude
Some programmer dude

Reputation: 409136

To get a single character, use std::istream::get. This should work for getting newlines as well.

But instead of getting characters in a loop until you get a newline, why not just use something like std::getline:

std::string str;
std::getline(cin, str);

Or if you only want to get max three characters you can use std::istream::getline:

char ch[4];
cin.getline(ch, 4, '\n');

Upvotes: 6

Related Questions