declare and define exception c 2b 2b

1// using standard exceptions
2#include <iostream>
3#include <exception>
4using namespace std;
5
6class myexception: public exception {
7  virtual const char* what() const throw() {
8    return "My exception happened";
9  }
10} myex; // declare instance of "myexception" named "myex"
11
12int main () {
13  try {
14    throw myex; // alternatively use: throw myexception();
15  } catch (exception& e) { // to be more specific use: (myexception& e)
16    cout << e.what() << '\n';
17  }
18  return 0;
19}