Thread: Jumping into C++

For the problem "Make your calculator program perform computations in a separate function for each type ofcomputation." I have done this

Code:

#include <iostream>


using namespace std;
int add (int x, int y)
{
    return x+y;
}
int subtract(int x,int y)
{
    return x-y;
}
int divide(int x,int y)
{
    return x/y;
}
int multiply(int x,int y)
{
    return x*y;
}


int main()
{


  while (true)
  {
      int x;
  int y;
  string arg;
  cout<<"please enter a number";
  cin>>x;
  cout<<"enter argument";
  cin>>arg;
  cout<<"enter another number";
  cin>>y;


  if (arg=="+")
  {
      cout<<add(x,y);
      break;
  }
  else if (arg=="-")
  {
      cout<<subtract(x,y);
     break;
  }


  else if(arg=="*")
  {
     cout<<multiply(x,y);
     break;


  }


   else if(arg=="/")
   {


      cout<<divide(x,y);
       break;
      }
      else
      {
          cout<<"wrong input, enter again";


      }
  }
}

But its pretty much long. have I done it in the right process?? or there is a simpler way to do it??

Originally Posted by Lesshardtofind

You could use a switch statement. Also the word argument could be swapped with operator which would make more sense.

owh, thanks.. I have not learnt the switch statement yet. I will give it a try after chapter 8. thanx.

Originally Posted by Lesshardtofind

You could reduce all that code into

Code:

  switch(arg){
    case "+":  cout<<add(x,y);      break;
    case "-":  cout<<subtract(x,y); break;
    case "*":  cout<<multiply(x,y); break;
    case "/":  cout<<divide(x,y);   break;
    default:   cout<<"wrong input, enter again";
  }

I tried this, but compiler gives error that switch quantity not an integer.

Code:

#include <iostream>

using namespace std;
int add (int x, int y)
{
    return x+y;
}
int subtract(int x,int y)
{
    return x-y;
}
int divide(int x,int y)
{
    return x/y;
}
int multiply(int x,int y)
{
    return x*y;
}


int main()
{


  while (true)
  {
      int x;
  int y;
  string arg;
  cout<<"please enter a number";
  cin>>x;
  cout<<"enter argument";
  cin>>arg;
  cout<<"enter another number";
  cin>>y;


  switch(arg){
    case "+":  cout<<add(x,y);      break;
    case "-":  cout<<subtract(x,y); break;
    case "*":  cout<<multiply(x,y); break;
    case "/":  cout<<divide(x,y);   break;
    default:   cout<<"wrong input, enter again";
  }
  }
}

Originally Posted by Lesshardtofind

Code:

    case "+":  cout<<add(x,y);      break;

Change all the double quotes to single.
And the arg to a char instead of a string (or switch arg[0]) .

Originally Posted by manasij7479

Change all the double quotes to single.
And the arg to a char instead of a string (or switch arg[0]) .

I tried this, but it seems to form an infinite loop if i enter a letter.

Originally Posted by Tamim Ad Dari

I tried this, but it seems to form an infinite loop if i enter a letter.

Post your current code.

Originally Posted by manasij7479

Post your current code.

Code:

#include <iostream>

using namespace std;
int add (int x, int y)
{
    return x+y;
}
int subtract(int x,int y)
{
    return x-y;
}
int divide(int x,int y)
{
    return x/y;
}
int multiply(int x,int y)
{
    return x*y;
}


int main()
{


  while (true)
  {
      int x;
  int y;
  char arg;
  cout<<"please enter a number";
  cin>>x;
  cout<<"enter argument";
  cin>>arg;
  cout<<"enter another number";
  cin>>y;


  switch(arg){
    case '+':  cout<<add(x,y);      break;
    case '-':  cout<<subtract(x,y); break;
    case '*':  cout<<multiply(x,y); break;
    case '/':  cout<<divide(x,y);   break;
    default:   cout<<"wrong input, enter again";
  }
  }
}

Try this after the inputs happen:

Code:

        if(!cin)
        {
            cin.clear();
            cin.ignore();
            continue;
        }

You should be able to write a nice wrapper function for this (or one to get an integer, which doesn't return until this check succeeds).