How can I fix this error? Go to case label crosses initialization

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  • Error: Jump to case label 3 answers

I have the following error in my Calculator code and do not understand how to correct it. Please any advice would be helpful.

ERROR: error: jump to case label [-fpermissive]| error:crosses initialization of 'int sum'| error: 'exit' was not declared in this scope|

CODE:

#include <iostream>
#include <cmath>
using namespace std;
void display_menu();
int get_menu_choice();
void get_two_numbers(int &a, int &b);
int add(int a, int b);
int subtract(int a, int b);

int main()
 {
 int choice;

  do
   {
    display_menu();
    choice = get_menu_choice();
    int x, y;
    switch (choice)
    {
        case 1: get_two_numbers(x, y);
                int sum = add(x, y);
                cout << x << " + " << y << " = " <<  sum << endl;
                break;
        case 2: get_two_numbers(x, y);
                int diff = subtract(x, y);
                cout << x << " - " << y << " = " <<  diff << endl;
                break;
        default:;
    }

     } while (choice != 3);

     cout << "Good bye...now." << endl;

     return 0;
       }

 void display_menu()
  {
   cout << endl;
   cout << "Simple Calculator Menu" << endl;
   cout << "----------------------" << endl;
   cout << " 1. Addition (+) " << endl;
   cout << " 2. Subtraction (-) " << endl;
   cout << " 3. Quit to exit the program" << endl;
   cout << endl;
  }

 int get_menu_choice()
  {
   int choice;
   cout << "Enter your selection (1, 2, or 3): ";
   cin >> choice;

  while(((choice < 1) || (choice > 3)) && (!cin.fail()))
   {
    cout << "Try again (1, 2, or 3): ";
    cin >> choice;
    }
  if (cin.fail())
    {
      cout << "Error: exiting now ... " << endl;
      exit(1);
     }
   return choice;
    }

 void get_two_numbers(int &a, int &b)
  {
    cout << "Enter two integer numbers: ";
    cin >> a >> b;
  }

 int add(int a, int b)
  {
   return (a + b);
  }

 int subtract(int a, int b)
  {
    return (a - b);
  }


You are declaring new variables inside a case statement without creating an enclosing scope:

switch (choice)
{
    case 1: get_two_numbers(x, y);
            //* vv here vv *
            int sum = add(x, y);
            //* ^^ here ^^ */
            cout << x << " + " << y << " = " <<  sum << endl;
            break;
    case 2: get_two_numbers(x, y);
            //* vv here vv */
            int diff = subtract(x, y);
            //* ^^ here ^^ */
            cout << x << " - " << y << " = " <<  diff << endl;
            break;
    default:;
}

Here's how to fix it:

switch (choice)
{
    case 1:
        {
            get_two_numbers(x, y);
            int sum = add(x, y);
            cout << x << " + " << y << " = " <<  sum << endl;
        }
        break;
    case 2:
        {
            get_two_numbers(x, y);
            int diff = subtract(x, y);
            cout << x << " - " << y << " = " <<  diff << endl;
        }
        break;
    default:
        break;
}

Of course, the exact formatting of brackets and indentation is up to you.