尝试模拟向量时编译器错误C2106

I'm trying to write a fake vector for my class assignment, and I currently get an error in the member function pushBack. The compiler doesn't seem to like incrementing the SIZE variable which holds the number of elements in the "vector". Is there something I might need to fix? Your assistance would be highly appreciated for helping me with this, and any other problems you might happen to find.I'm trying to write a fake vector for my class