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# C++ Calculator

I am trying to make a calculator in C++ but I keep running into errors. Please help me.

Here is the code:

``````#include <iostream>
#include <cmath>
#include <string>

using namespace std;

int main()

{ //what the variables are
double calculation;
double sign;
double number1;
double number2;

//the questions
cout<<"Enter a Number"<< endl;
cin>> number1;

cout<<"Enter Another Number"<< endl;
cin>> number2;

cout<<"Enter what you would like to do with these numbers"<< endl;
cout<<"For example * to multiply, / to divide, - to subtract, and + to add"<< endl;
cin>> sign;

//the calculations and answer
if  {sign=*}
calculation=number1*number2;
cout<<number1<<"*"<<number2"="<<calculation<<endl;

if  {sign=/}
calculation=number1/number2;
cout<<number1<<"/"<<number2"="<<calculation<<endl;

if  {sign=-}
calculation=number1-number2;
cout<<number1<<"-"<<number2"="<<calculation<<endl;

else    {sign=+}
calculation=number1+number2;
cout<<number1<<"+"<<number2"="<<calculation<<endl;

return 0;
}
``````
4
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alfredgg
Newbie Poster
2 posts since Sep 2012
Reputation Points: 0
Skill Endorsements: 0

declare sign as a char and not a double cause it makes no sense to have sign defined as double when its a character you know? try that and it should work but say sign == '*' and ect for the other operators

Rzink92
Newbie Poster
8 posts since Nov 2011
Reputation Points: 10
Skill Endorsements: 0

Your compiler should choke on that input. The diagnostics may or may not be useful, you have not indicated.
A proper `if` construct looks something like:

``````if (condition) {
// code for this condition
} else if (some_other_condition) {
// code here
} else {
// catch-all case in the if-else tree
}
``````

In your case you want your conditions to look like `variable == value` or, more specifically, `sign == '*'`

L7Sqr
Practically a Posting Shark
851 posts since Feb 2011
Reputation Points: 253
Skill Endorsements: 7

See The Tutorial At W3School....

itsolexpert
Newbie Poster
2 posts since Sep 2012
Reputation Points: 0
Skill Endorsements: 0

Thank you all for your advice. I finally got it to work!

alfredgg
Newbie Poster
2 posts since Sep 2012
Reputation Points: 0