若有以下程序:
include<iostream>
using namespace std;
class TestClass 1
{
public:
TestClass1()
{
X=0;
}
int x;
};
class TestClass2:virtual public TestClass1
{
public:
TestClass2()
{
x=10;
}
};
class TestClass3:virtual public TestClass 1
{
public:
TestClass3()
{
x=20;
}
};
class TestClass4:public TestClass2, protected TestClass3
{ };
int main()
{
TestClass4 obj;
cout<<obj.x<<end1;
return 0:
}
该程序运行后的输出结果是______。