Anh (Chị) hãy cho biết, chương trình sau sai ở dòng nào?
1. class
CVector
{
2. int x,y;
3. public :
4. CVector () {}
5. CVector (int,int);
6. CVector operator+ (CVector);
7. }
8. CVector::CVector (int a,int b) {
9. x = a;
10. y = b;
11. }
12. CVector CVector::operator+ (CVector v) {
13. CVector tmp;
14. tmp.x = x % v.x;
15. tmp.y = y % v.y;
16. return tmp;
17.}
18 .int main () {
19. CVector a (3,1);
20. CVector b(8,4);
21. CVector c;
22. c = a + b;
23. cout << c.x + c.y << endl;
24. return 0;
25.}