Imperial units

[xxvms]

Hi there :)

I am again working on example from book and something does not add-up literally ;) i think.... I don't know imperial units to well but as far as I understand
in 1 feet there is 12 inches.

in example from book I have this code

  // ReturningStructureVariables.cpp : Defines the entry point for the console application.
//

#include <iostream>
struct distance
{
	int feet;
	double inches;
};

distance addEngl(distance, distance);
void englDisp(distance);

int main()
{
	distance d1, d2, d3;	// define 3 lenghts
							//get lenght from user
	std::cout << "1st user Enter feet: ";
	std::cin >> d1.feet;
	std::cout << "1st user Enter inches: ";
	std::cin >> d1.inches;
	//same for 2nd user

	std::cout << "2nd user Enter feet: ";
	std::cin >> d2.feet;
	std::cout << "2nd user Enter inches: ";
	std::cin >> d2.inches;

	d3 = addEngl(d1, d2); //d3 is sum of d1 and d2
	std::cout << std::endl;
	englDisp(d1); //display all lenghts
	std::cout << " + ";
	englDisp(d2);
	std::cout << " = ";
	englDisp(d3);
	std::cout << std::endl;

	system("pause");
    return 0;
}
// addEngl()
// adds two structures of tyep Distance, returns sum

distance addEngl(distance dd1, distance dd2)
{
	distance dd3; // define a new structure for sum

	dd3.inches = dd1.inches + dd2.inches; // add the inches
	dd3.feet = 0; // for possible carry (i think if inches go over size 12 then it will be converted to 1 feet for each 12 inches
	if (dd3.inches >= 12.0) //if inches >= 12.0,
	{
		dd3.inches -= 12.0; // decrease inches by 12.0 and increase
		dd3.feet++; // feet by 1
	}
	dd3.feet += dd1.feet + dd2.feet; // add the feet dd3.feet = dd3.fett + dd1.feet + dd2.feet;
	return dd3;
}
//englDisp()
// display structures of type Distance in feet and inches
void englDisp(distance dd)
{
	std::cout << dd.feet << "\' - " << dd.inches << "\" ";
}

however, when I add 23 feet plus 12 inches and for second user 23 feet and 13 inches I am getting result
47 Feet and 13 inches. Should that be 48 Feet and 1 inch????

thanks :)

[jlb]

Look at this snippet:

if (dd3.inches >= 12.0) //if inches >= 12.0,
	{
		dd3.inches -= 12.0; // decrease inches by 12.0 and increase
		dd3.feet++; // feet by 1
	}

Remember you have dd3.inches == 25 at this point.

Perhaps you meant to use a while statement here instead?

[jonnin]

google can convert for you but really fast, since I was born using imperial...

12 inches is 1 foot. therefore 23 feet + 12 inches = 24 feet.
also, 1 inch is 2.54 cm exact, if you need to go metric later.
a yard is 3 feet, may also be useful to know.

23 feet + 13 inches is 24+1

the sum of 23 . 12 and 23.13 is 48.1 .. as above, its 24 feet for the first user, 24 and 1 inch for 2nd, and the sum of THOSE is 48 &1

[jonnin]

Oh, and code-wise, the easy thing to do is convert all data to inches, store only inches, and only deal with feet when you do output.

so convert 23 feet to 23*12 inches and store THAT + whatever left over inches. Its just easier to code the class this way, IMHO.

Then when printing, just do inches%12 is feet and inches/12 (integer) to get the values.

Finally, be aware that imperial users want to deal with inches in binary (powers of 2) fractions. It is common to talk about 1/2, 1/4, ... 1/32 inches. Beyond 1/32 is rare.

[xxvms]

Thanks Jlb and Jonnin

Jlb - nope its if statement only, if you have access to the book Object Orientated Programming in C++ 4th Edition. I was thinking about using a loop to get correct result but Jonning suggestion I think solve this problem in a neat way. Plus my lack of proper understanding of the imperial units does not help as well :D

Jonnin I know google converts but only if to one value so I will get result in inches or in feet with floating point

thank you both!