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”.

Answer 1

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;
}