reading from stdin

[momukhtar]

Hi

I want to read a string of unknown length from stdin. I tried to follow the approach from this link.

http://www.cplusplus.com/reference/string/string/getline/

My code is like this:

#include <iostream>
#include <string>

using namespace std;

int n;
cin >> n;
cout << "The value of n is " << n << endl;
    
string str;
getline(cin, str);
    
cout << "The entereed string is " << str << endl;

What I have noticed is that if I take integer input from cin (cin >> n;) in the above code before getline, the control does not stop on getline to take str as input from the console. If I don't do (cin >> n) before getline then the control stops on getline and takes the string as input.

Can someone please explain this behavior?

What is the best way to read from console multiple strings of unknown length in combination with the integers?

[Computergeek01]

Can someone please explain this behavior?

This is because the extraction operator delimits on white space, such as the return carriage, but it does not remove it from the buffer. The function "getline()" also delimits on white space by default, so it sees the return carriage in the buffer and does what it is supposed to. Either flush your input with 'std::cin.ignore()' or just use 'getline()' since it extracts the white space.

[MiiNiPaa]

Obligatory link:
http://stackoverflow.com/questions/21567291/why-does-stdgetline-skip-input-after-a-formatted-extraction

[momukhtar]

Thanks "Computergeek" and MiniPaa for the insights.

[bofafiller]

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[Duthomhas]

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Is there a reason you are derailing this thread?