Question

Is there an elegant way to remove characters from a string?
For instance, how do I get from foo123bar a string 123?

I’m aware that there are some similar questions, but my point is, that I don’t know a priori if foo or bar is present.

Cheers!

Answer 1

Use std::remove_if algorithm
Here is code:

#include <string>
#include <algorithm>
#include <iostream>
int main(int argc, char**argv)
{
  std::string str("hello123");
  str.erase(std::remove_if(str.begin(),str.end(),isalpha),str.end());
  std::cout<<str<<std::endl;
  return 0;
}

output will be:

123