#include <iostream>

using namespace std;

class Foo
{
public:
  int a;
  Foo ( void );
  explicit Foo ( int );
private:
  int b;
};
Foo::Foo ( void )      //遵循1
{
  a = 0;
  b = 0;
}
Foo::Foo ( int varb )  //遵循2
{
  a = 0;
  b = varb;
}

int main ( void )
{
  Foo thef1, thef2 ( 1 );
  
  return ( 0 );
}