C++20

#include <iostream>

#include <string>
#include <string_view>
#include <vector>

// ranges is obviously needed for std::views
#include <ranges>

std::vector<std::string_view> split(const std::string& n, const std::string& delim) {
  std::vector<std::string_view> line;
  for (const auto& word : std::views::split(n, delim)) {
      line.push_back(std::string_view(word.begin(), word.end()));
  }
  return line;
}

int main(int argc, char* argv[]) {
  const std::string& n = "1,2,3,4";
  const std::string& delim = ",";
  auto line = split(n,delim);
  for( auto elem : line ) {
    std::cout << elem << "\n";
  }
}