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How do I iterate over the words of a string?

Submitted by: @import:stackoverflow-api·Mar 10, 2026·

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howtheoveriteratewordsstring

Problem

How do I iterate over the words of a string composed of words separated by whitespace?

Note that I'm not interested in C string functions or that kind of character manipulation/access. I prefer elegance over efficiency. My current solution:

#include 
#include 
#include 

using namespace std;

int main() {
    string s = "Somewhere down the road";
    istringstream iss(s);

    do {
        string subs;
        iss >> subs;
        cout << "Substring: " << subs << endl;
    } while (iss);
}

Solution

For what it's worth, here's another way to extract tokens from an input string, relying only on standard library facilities. It's an example of the power and elegance behind the design of the STL.

#include 
#include 
#include 
#include 
#include 

int main() {
    using namespace std;
    string sentence = "And I feel fine...";
    istringstream iss(sentence);
    copy(istream_iterator(iss),
         istream_iterator(),
         ostream_iterator(cout, "\n"));
}

Instead of copying the extracted tokens to an output stream, one could insert them into a container, using the same generic copy algorithm.

vector tokens;
copy(istream_iterator(iss),
     istream_iterator(),
     back_inserter(tokens));

... or create the vector directly:

vector tokens{istream_iterator{iss},
                      istream_iterator{}};

Code Snippets

#include <iostream>
#include <string>
#include <sstream>
#include <algorithm>
#include <iterator>

int main() {
    using namespace std;
    string sentence = "And I feel fine...";
    istringstream iss(sentence);
    copy(istream_iterator<string>(iss),
         istream_iterator<string>(),
         ostream_iterator<string>(cout, "\n"));
}

vector<string> tokens;
copy(istream_iterator<string>(iss),
     istream_iterator<string>(),
     back_inserter(tokens));

vector<string> tokens{istream_iterator<string>{iss},
                      istream_iterator<string>{}};

Context

Stack Overflow Q#236129, score: 1513

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