C类返回旧值？

class test{
    public:
    int number;
    test(int pass){
      number = pass;
    }
};

int main(){
   test x(3);
   test y(2);
   test z[2]={x,y};
   y.number = 1;
   cout << "z[0].number: " << z[0].number << endl;
   cout << "z[1].number: " << z[1].number << endl;
   cout << "x.number: " << x.number << endl;
   cout << "y.number: " << y.number << endl;
   return 0;
}

得出这个输出,

z[0].number: 3
z[1].number: 2
x.number: 3
y.number: 1

而不是这个,

z[0].number: 3
z[1].number: 1
x.number: 3
y.number: 1

如何使第二个输出成为可能？我已经搜索了这三天,还没有运气:(