Thread: Polish form headache...

This will be the last question concerning my program.. So the user inputs a string like:

this + that + anotherOne - justoneMore

where this, that etc are classes containing a name and a vector of integers. How could I create another class which will hold the result? (The result will be a class with a vector whose elements are being added or substracting).

I got the names in a string vector and the operands in a char vector as well. I made a loop, but it works like this: it add this with that, then that with another one, and then it adds the two results...

I would appreciate a code.. at least for a simpler thing, such as a + b - c, where a , b, c are integers..

Why would you want a class for the result? Isn't the result just an int?

No, it's a class with a vector in which I store the sumation or the difference of the components.

If this, that, etc are objects, then the result is the same type of object as this, that, etc. And presumably you would define operator+ and operator- on those objects to add or subtract element-by-element.

I did that.... I even overloaded += so that I can have a temp class which does

Code:

 temp += this + that

. then it keeps adding.. but id does not add correctly..

Originally Posted by Veneficvs

I did that.... I even overloaded += so that I can have a temp class which does

Code:

 temp += this + that

. then it keeps adding.. but id does not add correctly..

Then you didn't do it right. Actually, temp += this + that is almost certainly wrong, unless you initialized temp to start with. But without actual code goodness, we're just flailing here.

Originally Posted by anon

What on earth are you talking about? o_O

Make a class overloading operator= and providing a constructor for conversion from this + that + anotherOne - justOneMore?

I will translate the code and post it here... I am too tired and freaking nervous now.... good night.

Here is the code

Code:

     CArray temp, first, second;
    for(contor = 0; contor < (int)simbols.size(); contor++)
    {
        if(simbols[contor] == '+')
        {
            for(i = 0; i < (int)arrays.size(); i++)
            {
                if(arrays[i].name == operations[contor])
                {
                    first = arrays[i];
                }
                if(arrays[i].name == operations[contor + 1])
                {
                    second = arrays[i];
                }
            }
            temp += (first + second);
        }
        if(simbols[contor] == '-')
        {
            temp += (first - second);
        }
    }

Consider the following input line:
first + second - third
Ok. Arrays is a vector of type CArray, which contains the name of the array and a vector of type int, for the components. Operations is a string vector containing first, second, third and any other array that might appear in the line. Simbols is a string vector that contains + and - in the order they appear in the input line. Temp is going to retain the result of those sumations or differences.

I am adding the arrays two by two ... but it acts like this: 1 + 2 + 3 should be 6... but it does 1+ 2, then 2 + 3, and then 1 + 2 + 2 + 3 , which is 8... So how could I properly adjust the loop to calculate what I want, please?..

As I stated above, temp += (first + second) is grossly incorrect. temp = first. temp += second. temp -= third.

If operator is plus, you should have "temp += second", and if operator is minus, you should have "temp -= second". Also, and this is big, you don't ever bother to initialize first and/or second in your '-' case. You'll need to walk through arrays just the same in '-' as you do in '+'.

Originally Posted by Veneficvs

I didn't do it because I tested with pluses. And it did not work for them..

What "doesn't work" about it?