#include <iostream>
using namespace std;
 
class Foo
{
  const int m_bar;				// can be initalized only once 
  int m_zoo;					// must be constructed (default possible) but can be overwritten
public:
  Foo(): m_bar(1), m_zoo(2) {}  // the constant can never be changed
  Foo(int i) 
   : Foo() {m_zoo=i;}			// you can still change in the body already constructed items
  Foo(int i, int j) : m_bar(i), m_zoo(j) {}   // comprehensive init  
  Foo(char a) : Foo(a,2) {};   // just delegate to the comprehensive version
  void show () { cout<<"bar="<<m_bar<<",zoo="<<m_zoo<<endl; }
};
 
int main() {
	Foo a, b(11), c(11,13), d('\r'); 
	a.show(); b.show(); c.show(); d.show(); 
	return 0;
}

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