Help with simple cin problem please.

[Shane]

So it's been a while since I've done anything in C++, but I thought I
could grab

cin >> input;

and it would go into string input, even if what's coming in happens to
be 3 words separated by spaces. I don't want to use c strings, I want
to use std::string.

So imagine the code

#include <iostream>

int main()
{
string input;

while(true)
{
cout << "Enter three words: ";
cin >> input;
cout << input;
}
}


So you would enter 3 words on the command line, but only one is spit
back at you because only the first one is stored in the string. Then
the loop continues and it actually picks up the next value for the
second loop, and so on.

What I want to happen is for input to store one string with three
words, etc.

Can someone help?

Shane

 

[Mark]

On 7 Jul 2004 17:08:21 -0700, (e-mail address removed) (Shane) wrote:

[...]

So you would enter 3 words on the command line, but only one is spit
back at you because only the first one is stored in the string. Then
the loop continues and it actually picks up the next value for the
second loop, and so on.

And it should.

What I want to happen is for input to store one string with three
words, etc.

Can someone help?

Have a look at getline

std::string input;
std::getline(std::cin, input);
std::cout << input << std::endl;

or
copy(istream_iterator<string>(cin),
istream_iterator<string>(),
ostream_iterator<string>(cout, " "));


Mark

 

[Matthew Del Buono]

So it's been a while since I've done anything in C++, but I thought I
could grab

cin >> input;

and it would go into string input, even if what's coming in happens to
be 3 words separated by spaces. I don't want to use c strings, I want
to use std::string.

So imagine the code

#include <iostream>

int main()
{
string input;

while(true)
{
cout << "Enter three words: ";
cin >> input;
cout << input;
}
}


So you would enter 3 words on the command line, but only one is spit
back at you because only the first one is stored in the string. Then
the loop continues and it actually picks up the next value for the
second loop, and so on.

What I want to happen is for input to store one string with three
words, etc.

Can someone help?

Shane

Instead of using cin, you might consider using getline:

getline(cin, input, ' ');

Note: This will only accept words separated by a space. If there is a
newline in there, it'll be lumped in with the word, so be careful.

-- Matt

 

[Shane]

On 7 Jul 2004 17:08:21 -0700, (e-mail address removed) (Shane) wrote:

[...]

So you would enter 3 words on the command line, but only one is spit
back at you because only the first one is stored in the string. Then
the loop continues and it actually picks up the next value for the
second loop, and so on.

And it should.

What I want to happen is for input to store one string with three
words, etc.

Can someone help?

Have a look at getline

std::string input;
std::getline(std::cin, input);
std::cout << input << std::endl;

or
copy(istream_iterator<string>(cin),
istream_iterator<string>(),
ostream_iterator<string>(cout, " "));


Mark

Thanks for the point in the right direction. That's exactly what I needed.

Shane