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  1. #include <iostream>
  2. #include <stack>
  3. #include <string>
  4. #include <climits>
  5. using namespace std;
  6.  
  7. void doOp(const char & e, stack <int>& myS)
  8. {
  9. 	if (myS.size() == 2)
  10. 	{
  11. 		cout << "Performing "<<e<<endl; 
  12.     	int num1, num2, answ;
  13.     	num2 = myS.top();
  14.     	myS.pop();
  15.     	num1 = myS.top();
  16.     	myS.pop();
  17.     	if (e == '+')
  18. 	        answ = num1 + num2;
  19. 	    else if (e == '-')
  20.         	answ = num1 - num2;
  21.     	else if (e == '*')
  22. 	        answ = num1 * num2;
  23. 	    else if (e == '/')
  24.         	answ = num1 / num2;
  25.     	else if (e == '%')
  26. 	        answ = num1 % num2;
  27. 	    else
  28.     	    cout << "\nError- Invalid operator" << endl;
  29.  
  30.     	cout << "\nCalculating..." << endl << answ << endl;
  31.     	myS.push(answ);
  32. 	}
  33. 	else
  34.     	cout << "\nInvalid stack size- too few, or too many" << endl;
  35. }
  36.  
  37. int main() {
  38. stack <int> calcStack;
  39. string exp;
  40. char ans;
  41. cout << "\nDo you want to use the calculator?" << endl;
  42. cin >> ans;
  43. while (ans == 'y' && cin)
  44. {
  45.     cin.ignore (INT_MAX, '\n');
  46.     cout << "\nEnter your exp" << endl;
  47.     getline (cin, exp); 
  48.     cout<< "Parsing: "<<exp<<endl; 
  49.     for (int i = 0; i < exp.size(); i++)
  50.     {
  51.         if (isspace(exp[i]))
  52.         {
  53.  
  54.         }
  55.         else if (isdigit(exp[i]))
  56.         {
  57.             int num = exp[i] - '0';
  58.             calcStack.push(num);
  59.             cout << "Pushed " << num<<endl; 
  60.         }
  61.         else
  62.             doOp(exp[i], calcStack);
  63.     }
  64.  
  65.     while (!calcStack.empty())
  66.     {
  67.         calcStack.pop();
  68.     }
  69.  
  70.     cout << "\nDo you want to use the calculator again?" << endl;
  71.     cin >> ans;
  72. }
  73.  
  74. return 0;
  75. }
  76.  
Success #stdin #stdout 0s 3424KB
comments ()
stdin 
y
54+2*
y
54+2z
stdout 
Do you want to use the calculator?

Enter your exp
Parsing: 54+2*
Pushed 5
Pushed 4
Performing +

Calculating...
9
Pushed 2
Performing *

Calculating...
18

Do you want to use the calculator again?

Enter your exp
Parsing: 54+2z
Pushed 5
Pushed 4
Performing +

Calculating...
9
Pushed 2
Performing z

Error- Invalid operator

Calculating...
-1216617139

Do you want to use the calculator again?
https://ideone.com/xELM9R
language:
C++14 (gcc 8.3)
created:
9 years ago
visibility:
public

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