Parsing a comma-delimited std::string


Question

If I have a std::string containing a comma-separated list of numbers, what's the simplest way to parse out the numbers and put them in an integer array?

I don't want to generalise this out into parsing anything else. Just a simple string of comma separated integer numbers such as "1,1,1,1,2,1,1,1,0".

1
119
12/12/2009 10:21:56 PM

Accepted Answer

Input one number at a time, and check whether the following character is ,. If so, discard it.

#include <vector>
#include <string>
#include <sstream>
#include <iostream>

int main()
{
    std::string str = "1,2,3,4,5,6";
    std::vector<int> vect;

    std::stringstream ss(str);

    for (int i; ss >> i;) {
        vect.push_back(i);    
        if (ss.peek() == ',')
            ss.ignore();
    }

    for (std::size_t i = 0; i < vect.size(); i++)
        std::cout << vect[i] << std::endl;
}
137
7/10/2019 7:09:00 AM

Something less verbose, std and takes anything separated by a comma.

stringstream ss( "1,1,1,1, or something else ,1,1,1,0" );
vector<string> result;

while( ss.good() )
{
    string substr;
    getline( ss, substr, ',' );
    result.push_back( substr );
}

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