Please help me with outputting the contents of my stack on the input line.

[ovaltine99]

fixed

[coder777]

I'd suggest to introduce another string which you show on line 18 and add variable + space to (after line 19). Reset it after compute

[ovaltine99]

Thanks for the tip but I'm a little confused on how I woudl go about resetting the string after "compute"?

[coder777]

you can use clear:

http://www.cplusplus.com/reference/string/string/clear/

or assign an empty string (x = "")

[ovaltine99]

On line 18 right now I have cout << "Enter: " << variable << " ";

What this does is output the previous variable I typed before the second input. When I add variable + space after line 19 like this

cout << "Enter: "; 
cin >> variable; 
cout << variable << " " << endl;

I get this

Enter: 1
1
Enter:2
2
Enter:3
3

I need to be able to have the stack on the same line as my input line. They can't be on separate lines.

Thanks!

[ovaltine99]

fixed

[ovaltine99]

Any help? Been stuck on this for a couple of hours now :(

[coder777]

Don't modify the stack just for output. My suggestion was to introdurce a new variable for the output. Like so:

int main()
{
  stack<double> rpnStack;
  string variable;
  string expression;
  
  while (true)
  {
    // collect user input
    cout << "Enter: " << expression;
    cin >> variable;
    expression += variable + " ";
    
    
    // get number
    double num;
    if(istringstream(variable) >> num) // input stream class to operate on strings
    {
      rpnStack.push(num);
    }
    
    // operator
    else if (operatorNum(variable))
    {
      compute(variable, rpnStack);
      expression.clear();
    }
    
    // when user quits "Q" or "q"
    else if(variable == "q" || "Q")
    {
      break;
    }
    
    // invalid output
    else
    {
      cout << "Try again" << endl;
    }

  }
  
}