Review, divide two integers

[TheJollyRoger]

Problem: "Write a value-returning function called isFactor. It should take 2 integer parameters and return true if the 2nd number can be divided by the 1st number evenly (in other words, if it has no remainder). So isFactor(4, 16) should return true because 16/4 = 4, but isFactor(4, 15) should return false because 15/4 = 3.75. Test it in int main()."

When I debug my code I get" error C4716: 'divide': must return a value", but I do not understand why I am getting that error.

bool divide(int x, int y)
{
	int rest = x / y;

	if (rest == 0)
		cout << "True" << endl;
	else
		cout << "False" << endl;
}
// main function
int main()
{
	int x;
	int y;
	

	//prompts user for input
	cout << "Input first value: " << endl;
	cin >> x;

	cout << "Input second value: " << endl;
	cin >> y;

	if
		(divide(x, y) == true)
		cout << y << "can be divided by " << x << endl;
	else
		cout << y << "can not be divided by " << x << endl;

	return 0;
}

[wolle]

When I debug my code I get" error C4716: 'divide': must return a value", but I do not understand why I am getting that error.

It's because you have declared the divide function to return a bool but it doesn't return anything.

You print a message to cout in divide but that's not the same as returning something. For that you need to use a return statement.

[Skeeterbreath]

It's because your divide function in not returning a value.

bool divide(int x, int y)
{
       if (x % y == 0)
              return true;
       else
              return false;
}

[TheJollyRoger]

Thanks. Now I've fixed that issue.

[wolle]

Thanks. Now I've fixed that issue.

Note that there's a distinction between integer types and floating point types in C++. Make sure you fully understand this distinction and the implications.

Regarding integer division. This,

int rest = x / y; // / gives quotient

will give you the quotient (not the rest) of x divided by y. This,

int rest = x % y; // % gives remainder

will give you the remainder (the rest) of x divided by y. if it is 0 then x is evenly divisible by y. That's what you should use in isFactor().