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Calculator help no output

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Join Date: Sep 2009

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infern0

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Calculator help no output

Oct 19th, 2009

Hi. I'm having trouble making a simple calculator.
The code I have so far compiles, but it does not run.
Right now I only have addition in because I wanted to make sure I was going in the right direction before I added anything else.
I have to use a Do...while statement in this code.
Can anyone tell me when the program doesn't run???
Here is what I have so far:

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 C++ Syntax (Toggle Plain Text) 
#include <iostream>
#include <string>
using namespace std;
 
int main ()
{
	char sign;
	string input;
	string total=0;
	cout << "Current total is 0" << endl;
	do
	{	cout << "Enter an operation: + - * / (or enter X to exit):";
		cin >> sign;
		if (sign = '+')
			cout <<"Enter a number: ";
			cin >> input;
			cout <<"Current total is " << input + total;
	}
		while (input != "X");
}
#include <iostream>
#include <string>
using namespace std;

int main ()
{
	char sign;
	string input;
	string total=0;
	cout << "Current total is 0" << endl;
	do
	{	cout << "Enter an operation: + - * / (or enter X to exit):";
		cin >> sign;
		if (sign = '+')
			cout <<"Enter a number: ";
			cin >> input;
			cout <<"Current total is " << input + total;
	}
		while (input != "X");
}

Thanks in advance.

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Join Date: Jan 2009

Posts: 151

Reputation: Phil++ is an unknown quantity at this point

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Phil++

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Oct 19th, 2009

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <iostream>
#include <string>
using namespace std;
 
int main ()
{
	char sign;
	string input;
	int total=0; // No need for a string, is there?
	cout << "Current total is 0" << endl;
	do
	{	cout << "Enter an operation: + - * / (or enter X to exit):";
		cin >> sign;
		if (sign == '+')
                {
 	                cout <<"Enter a number: ";
			cin >> input;
			cout <<"Current total is " << input + total;
                 }
	}while (input != "X");
}
#include <iostream>
#include <string>
using namespace std;
 
int main ()
{
	char sign;
	string input;
	int total=0; // No need for a string, is there?
	cout << "Current total is 0" << endl;
	do
	{	cout << "Enter an operation: + - * / (or enter X to exit):";
		cin >> sign;
		if (sign == '+')
                {
 	                cout <<"Enter a number: ";
			cin >> input;
			cout <<"Current total is " << input + total;
                 }
	}while (input != "X");
}

I wouldn't use string unless you know how to use it. Use char arrays.

Last edited by Phil++; Oct 19th, 2009 at 7:07 pm.

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Join Date: Apr 2004

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Dave Sinkula Dave Sinkula is offline

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long time no c

Oct 19th, 2009

Some starters: Sort out your confusion about strings and numbers. Assignment is = , comparison is == . Multiline blocks are not determined by indentation in this curly-brace language.

Last edited by Dave Sinkula; Oct 19th, 2009 at 7:08 pm. Reason: D'oh! Pokey again.

"One of the methods used by statists to destroy capitalism consists in establishing controls that tie a given industry hand and foot, making it unable to solve its problems, then declaring that freedom has failed and stronger controls are necessary." --Ayn Rand

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Join Date: Sep 2009

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infern0

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Oct 19th, 2009

I don't know how to use arrarys yet

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Join Date: Sep 2009

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infern0

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Oct 19th, 2009

•

Originally Posted by Dave Sinkula

Some starters: Sort out your confusion about strings and numbers. Assignment is = , comparison is == . Multiline blocks are not determined by indentation in this curly-brace language.

I was trying to use double to identify the input..but I can't use "X" because it is not a number.

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Join Date: Jan 2009

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Reputation: Phil++ is an unknown quantity at this point

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Phil++

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Oct 19th, 2009

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <iostream>
#include <string>
using namespace std;
 
int main ()
{
	char sign;
	int input;
	int total=0; // No need for a string, is there?
	cout << "Current total is 0" << endl;
	do
	{	cout << "Enter an operation: + - * / (or enter X to exit):";
		cin >> sign;
		if (sign == '+')
                {
 	                cout <<"Enter a number: ";
			cin >> input;
			cout <<"Current total is " << input + total;
                 }
	}while (input != "X");
}
#include <iostream>
#include <string>
using namespace std;
 
int main ()
{
	char sign;
	int input;
	int total=0; // No need for a string, is there?
	cout << "Current total is 0" << endl;
	do
	{	cout << "Enter an operation: + - * / (or enter X to exit):";
		cin >> sign;
		if (sign == '+')
                {
 	                cout <<"Enter a number: ";
			cin >> input;
			cout <<"Current total is " << input + total;
                 }
	}while (input != "X");
}

Actually, there is no need to use string since you're only inputting a number. Char array:

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char name[255];
char name[255];

Strings:

Help with Code Tags

C++ Syntax (Toggle Plain Text)

string sentence = "Hello my name is Phil and I hate C++";

where as using single char, would just print out "H"

Last edited by Phil++; Oct 19th, 2009 at 7:13 pm.

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Join Date: Apr 2004

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Dave Sinkula Dave Sinkula is offline

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long time no c

Oct 19th, 2009

•

Originally Posted by infern0

I was trying to use double to identify the input..but I can't use "X" because it is not a number.

So take input as a string, and if it's not "X", then convert it to a number.

Last edited by Dave Sinkula; Oct 19th, 2009 at 7:14 pm. Reason: Slow on the draw again; added quote.

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infern0

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Oct 19th, 2009

•

Originally Posted by Dave Sinkula

So take input as a string, and if it's not "X", then convert it to a number.

I don't know how to convert a string to a number.. I tried looking it up but it looks complicated.

Getting 10 errors in the build current. I think it's because of the input problem with the while statement.

Last edited by infern0; Oct 19th, 2009 at 7:24 pm.

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Join Date: Jan 2009

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Phil++

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Oct 19th, 2009

What errors?

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Join Date: Apr 2004

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Dave Sinkula Dave Sinkula is offline

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long time no c

#10

Oct 19th, 2009

•

Originally Posted by infern0

I don't know how to convert a string to a number.. I tried looking it up but it looks complicated.

Getting 10 errors in the build current. I think it's because of the input problem with the while statement.

Converting a string to a number is just about the most frequently asked question. Surely even a rudimentary search would give you a hint. (Part of learning to code is learning how to find answers. This is a good time to start, I'd say.)