Sams Teach Yourself C++ in 21 Days

Answers 841

D

32:

33: SimpleCircle::SimpleCircle(const SimpleCircle & rhs)

34: {

35: int val = rhs.GetRadius();

36: itsRadius = new int(val);

37: }

38:

39: SimpleCircle& SimpleCircle::operator=(const SimpleCircle & rhs)

40: {

41: if (this == &rhs)

42: return *this;

43: *itsRadius = rhs.GetRadius();

44: return *this;

45: }

46:

47: const SimpleCircle& SimpleCircle::operator++()

48: {

49: ++(*itsRadius);

50: return *this;

51: }

52:

53: // Operator ++(int) postfix.

54: // Fetch then increment

55: const SimpleCircle SimpleCircle::operator++ (int)

56: {

57: // declare local SimpleCircle and initialize to value of *this

58: SimpleCircle temp(*this);

59: ++(*itsRadius);

60: return temp;

61: }

62: int SimpleCircle::GetRadius() const

63: {

64: return *itsRadius;

65: }

66: int main()

67: {

68: SimpleCircle CircleOne, CircleTwo(9);

69: CircleOne++;

70: ++CircleTwo;

71: cout << “CircleOne: “ << CircleOne.GetRadius() << endl;

72: cout << “CircleTwo: “ << CircleTwo.GetRadius() << endl;

73: CircleOne = CircleTwo;

74: cout << “CircleOne: “ << CircleOne.GetRadius() << endl;

75: cout << “CircleTwo: “ << CircleTwo.GetRadius() << endl;

76: return 0;

77: }

9. You must check to see whether rhsequals this, or the call to a = awill crash
   your program.

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