cstdiofile::readstring question

[s|lent]

Hello all

I have 2 txt files: text.txt, and text2.txt.

Text.txt contains this:

ddddsd, 1111, sdsdss,  22222
ddddsd, 1111, sdsdss,  22222
ddddsd, 1111, sdsdss,  22222

and text2.txt is an empty file.

What I want is to read only the numbers from the first file and write them into the second file. How can i achieve this? What Ive written so far works, except that it takes all the contents of the first file and places it into the 2nd (i only need the numbers though).

#include <afx.h>

using namespace std;

int main()
{
CStdioFile fisierRead, fisierWrite;
CString s;

fisierRead.Open(_T("C:\\text.txt"), CFile::modeRead|CFile::typeText);
fisierWrite.Open(_T("C:\\text2.txt"), CFile::modeWrite|CFile::modeCreate);
	
while(fisierRead.ReadString(s))
{
	fisierWrite.WriteString(s+ L"\n");

}
return 0;
}

so how can i only read the numbers?

thank u
PS - i dont need code only a hint