Comments on: 1.10a — How to design your first programs

By: Andrew_Hicks

Andrew_Hicks — Wed, 04 Jan 2012 21:32:11 +0000

What is the reason for adding

#include

i deleted it for the calculator that you made and it still worked, i was wondering if it was just added to be sure or if i’m missing something?

By: Ascendancy

Ascendancy — Wed, 28 Dec 2011 12:13:57 +0000

Silly me, I posted the comment in the wrong section. It was meant to be posted in section 1.11.

By: Ascendancy

Ascendancy — Wed, 28 Dec 2011 12:10:58 +0000

Haha, I ended up with an answer almost identical to Alex’s. I used a header file for the first question; who cares if I didn’t read every question thoroughly, I used the best method for the job.

By: zingmars

zingmars — Mon, 19 Sep 2011 16:29:16 +0000

You need to use two equality signs (“=”) when comparing something.
A single sign is an assignment.

By: Hex

Hex — Sat, 17 Sep 2011 17:00:19 +0000

int Calculate(int, char, int)
{
if (Operation = ‘+’)
return Number1+Number2;

if (Operation = ‘-’)
return Number1-Number2;

if (Operation = ‘*’)
return Number1*Number2;

if (Operation = ‘/’)
return Number1/Number2;

return (0);
}
my code wont do any thing but add. What have i done wrong.

By: Maksism

Maksism — Sun, 21 Aug 2011 06:40:37 +0000

#include "stdafx.h"
#include 

using namespace std;

int GetNumber1()
{
	cout << "Please type in number ";
	int nX;
	cin >> nX;
	return nX;
	}

char GetMathOperation()
{
	cout << "Please enter + - * /"; 
	char cOp;
	cin >> cOp;
	return cOp;
}

int GetNumber2()
{
	cout << "Please type in number ";
	int nY;
	cin >> nY;
	return nY;
}

int CalResults(int nX, char cOp, int nY)
{
	if (cOp=='+')
		return nX + nY;
	if (cOp=='-')
		return nX - nY;
	if (cOp=='*')
		return nX * nY;
	if (cOp=='/')
		return nX / nY;

	return 0;
}

void PrintResults(int nResult)
{
	cout << "The answer is " << nResult << endl;
}
int main()
{
	int nX = GetNumber1();
	char cOp = GetMathOperation();
	int nY = GetNumber2();
	int nResult = CalResults(nX, cOp, nY);
	PrintResults(nResult);
	cin.clear();
	cin.ignore(255, '\n');
	cin.get();
}

Finally got it

By: zingmars

zingmars — Sat, 20 Aug 2011 15:36:45 +0000

@Chris – Gravatar.
@Kostas81 – when you call on the writenumber, it copies the value of whatever you send to the function, defines it as ‘c’, uses it, and at the end of the function it destroys the value, if that was what you were asking.

By: Chris

Chris — Mon, 25 Jul 2011 20:50:56 +0000

Hey, how did you set your avatar? I dont see any option for that in my profile settings.

By: Chris

Chris — Mon, 25 Jul 2011 20:50:14 +0000

Yeah, i need to go through these tutorials again. Im going through them fast, too much information lol.

By: Kostas81

Kostas81 — Mon, 25 Jul 2011 16:37:22 +0000

I think you are right. The variables nX and nY are defined and used localy inside
int CalculateResult(int nX, char chOperation, int nY). But it is the caller, that is, main(), which decides which the variables are, and the decision is nX = nInput1 and nY = nInput2. (It could be just a number, as for example nX = 3 and nY = 5, as in a previous example. But here the number is the integer given from the user as input. The first number is assigned to nInput1 and the second to nInput2. And then, main() uses int CalculateResult(nInput1, chOperation, nInput2).

This is the simplest way I can explain what I think …

Thank you for your reply!