c++ parse getline in dynamic array - c++

Question

I already asked, how I can parse single words from a stream into variables, and that works perfectly, but I don't know how many words the user will give as input. I thought I could parse it into a dynamic array, but I don't know where to start. How can I write "for each word in line"?
This is how I parse the words into the vars:
string line;
getline( cin, line );
istringstream parse( line );
string first, second, third;
parse >> first >> second >> third;
Thanks!
EDIT: Thanks to all of you, I think I get it know... and it works!

Answer 1

You could use std::vector<std::string> or std::list<std::string> -- they handle the resizing automatically.
istringstream parse( line );
vector<string> v;
string data;
while (parse >> data) {
v.push_back(data);
}

Answer 2

A possibility would be to use std::vector with istream_iterator:
#include <iostream>
#include <sstream>
#include <vector>
#include <iterator>
#include <algorithm>
int main()
{
std::istringstream in(std::string("a line from file"));
std::vector<std::string> words;
std::copy(std::istream_iterator<std::string>(in),
std::istream_iterator<std::string>(),
std::back_inserter(words));
return 0;
}
The vector will grow as required to store whatever number of words is provided by the user.

Answer 3

You can write as follows:
string line;
getline( cin, line );
istringstream parse( line );
string word;
while (parse >> word)
// do something with word

Answer 4

Since you tagged the question with foreach, here's a way to do it with with standard for_each algorithm and C++11 lambdas:
#include <string>
#include <sstream>
#include <iostream>
#include <algorithm> // for for_each
#include <vector> // vector, obviously
#include <iterator> // istream_iterator
using namespace std;
int main()
{
string line;
vector<string> vec;
getline(cin, line);
istringstream parse(line);
for_each(
istream_iterator<string>(parse),
istream_iterator<string>(),
// third argument to for_each is a lambda function
[](const string& str) {
// do whatever you want with/to the string
vec.push_back(str); // push it to the vector
}
);
}
A vector is exactly what you asked for - a dynamically resizable array that you should almost always prefer over C-style arrays. It's size need not to be known at compile time.