C++构造函数

class testint  
{
public:
	testint();
	testint(int b);
	//testint(testint& another);
	 ~testint();
private:
	int i;
};
////////////////
testint::testint()
{
	cout<<"construct"<<endl;
}
testint::testint(int b):i(b)
{
	cout<<"construct by " << i<<endl;
}

testint::~testint()
{
	cout<<"destruct i is "<<i<<endl;
}
///////////////
testint play(testint a)
{
	return a;
}
////
int main(int argc, char* argv[])
{
	//printf("Hello World!\n");
	testint t1 = play(4);
	testint t2 = play(5);
	testint t3 = play(t1);
	return 0;
}
///
输出结果为：
construct by 4
destruct i is 4
construct by 5
destruct i is 5
destruct i is 4
destruct i is 4
destruct i is 5
destruct i is 4
///