std::cin input with spaces?

Question

#include <string>

std::string input;
std::cin >> input;

The user wants to enter "Hello World". But cin fails at the space between the two words. How can I make cin take in the whole of Hello World?

I'm actually doing this with structs and cin.getline doesn't seem to work. Here's my code:

struct cd
{
    std::string CDTitle[50];
    std::string Artist[50];
    int number_of_songs[50];
};

std::cin.getline(library.number_of_songs[libNumber], 250);

This yields an error. Any ideas?

Answer 1

You have to use cin.getline():

char input[100];
cin.getline(input,sizeof(input));

Answer 2

It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".

Use std::getline:

#include <string>
#include <iostream>

int main()
{
   std::string name, title;
   
   std::cout << "Enter your name: ";
   std::getline(std::cin, name);
   
   std::cout << "Enter your favourite movie: ";
   std::getline(std::cin, title);
   
   std::cout << name << "'s favourite movie is " << title;
}

Note that this is not the same as std::istream::getline, which works with C-style char buffers rather than std::strings.

Update

Your edited question bears little resemblance to the original.

You were trying to getline into an int, not a string or character buffer. The formatting operations of streams only work with operator<< and operator>>. Either use one of them (and tweak accordingly for multi-word input), or use getline and lexically convert to int after-the-fact.

Answer 3

The Standard Library provides an input function called ws, which consumes whitespace from an input stream. You can use it like this:

std::string s;
std::getline(std::cin >> std::ws, s);

Answer 4

Use :

getline(cin, input);

the function can be found in

#include <string>

Answer 5

You want to use the .getline function in cin.

#include <iostream>
using namespace std;

int main () {
  char name[256], title[256];

  cout << "Enter your name: ";
  cin.getline (name,256);

  cout << "Enter your favourite movie: ";
  cin.getline (title,256);

  cout << name << "'s favourite movie is " << title;

  return 0;
}

Took the example from here. Check it out for more info and examples.

Answer 6

THE C WAY

You can use gets function found in cstdio(stdio.h in c):

#include<cstdio>
int main(){

char name[256];
gets(name); // for input
puts(name);// for printing 
}

THE C++ WAY

gets is removed in c++11.

[Recommended]:You can use getline(cin,name) which is in string.h or cin.getline(name,256) which is in iostream itself.

#include<iostream>
#include<string>
using namespace std;
int main(){

char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}

Answer 7

How do I read a string from input?

You can read a single, whitespace terminated word with std::cin like this:

#include<iostream>
#include<string>
using namespace std;

int main()
{
    cout << "Please enter a word:\n";

    string s;
    cin>>s;

    cout << "You entered " << s << '\n';
}

Note that there is no explicit memory management and no fixed-sized buffer that you could possibly overflow. If you really need a whole line (and not just a single word) you can do this:

#include<iostream>
#include<string>
using namespace std;

int main()
{
    cout << "Please enter a line:\n";

    string s;
    getline(cin,s);

    cout << "You entered " << s << '\n';
}

Answer 8

I rather use the following method to get the input:

#include <iostream>
#include <string>

using namespace std;

int main(void) {
    string name;

    cout << "Hello, Input your name please: ";
    getline(cin, name);

    return 0;
}

It's actually super easy to use rather than defining the total length of array for a string which contains a space character.