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Regex to capture both digit values in string

mrpear2020 (58)
Imagine I will be reading an XML file. Like the lines used in the example below. I need to capture the value of x and y for each line. If possible, avoiding an iterator. Can you please give me a hint on how to solve this (if possible without an iterator).



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#include <iostream>
#include <regex>
#include <string>
 
using namespace std;

int main()
{   
    int x;
    int y;
    
    string example1= "<Point x=\"0\" y=\"1\" />";
    string example2= "       x=\"2\" y=\"3\" />";
    string example3= "</Point>";
   
    const std::regex re("(\"([0-9]+)\")");
    
    std::smatch sm;
    if (std::regex_search(example1, sm, re))
    {
        //Match is working to detect numbers
        cout << "Match!";
        //Now I would expect to print 0, 1 for example:
        cout << sm[1];
        cout << sm[1];
       
    }
    
    
    return 0;
}
jonnin (11437)
there are a lot of ways to do it avoiding iterators; you can append a '\0' and use strstr on a string variable, which is a lot like find without the iterators.
search for x=, search again for your \" pair and extract between the pair, that is your number.

its probably doable with regx too, but I do not use those enough and it takes me a bit to nail down the symbols needed to make it do what I want. you are on your own there but its certainly doable.
Last edited on
andywestken (4094)
Is this for an exercise? If not, why not use an XML parser?

Andy
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