   Problem overloading operator -
  Hello all.I'm currently trying to learn Cplusplus (wont let me do the plus sign :S ) and its been going really well so far.But now it seems i've run into a problem that i can't figure out.I'm overloading operators and the problem is with the operator -.I've done:private:    int x;    int y;    int z;public:friend T1 operator -(const  T1& a, const T2& b);//Then:T1 operator -(const  T1& a, const T2& b){    T1 temp;    temp.x = a.x - b.x;    temp.y = a.y - b.y;    temp.z = a.z - b.z;    return temp;}//Then in my main function I've got:aObj = aObj - T1(0,0,10);  //this works.aObj = T1(10,0,0) - T1(0,0,5);  //this dosn't work.anyone here that can tell me why aObj = T1(10,0,0) - T1(0,0,5); dosn't work?   
  How does it not work? What is the result? Also, are you sure your constructor is working correctly?   ;  What I do is cout << aObj.That prints out x, y, z to the screen.if I comment out the line that dosnt work, everything compiles and runs no problem.if i try to compile with the line that gives error it wont compile.it says: '-' : undeclared identifier   ;  Post the actual code that demonstrates the problem.   ;  Found out what the problem was. I got the content of the main.cpp file from the teacher in a pdf file. So I just copied the text from there and pasted into VS2010. All I had to do to fix the problem was delete the - and retype it. :P   