Alternatives of switch [closed] - c++

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In the below code, I need help with the alternatives of switch case, I mean how can I avoid switch and use the other option to execute the code.
Code:
cout << " *********************Intensive Program 1***********************\n\n" << endl;
cout << "\nHere's the menu of choices: ";
cout << "\n1. Add a Circle.\n";
cout << "2. Print a Circle. \n";
cout << "3. Print all Cricles \n";
cout << "4. Exit.\n";
cout << "\nPlease enter your choice: ";
cin >> choice;
while (choice <4){
switch (choice){
case 1:
// For adding cirles to the class
cout << " Enter the value for the radius of the circle: ";
cin >> radius;
cout << " Enter the value for the center of the circle: ";
cin >> center;
myCircle[thisPosition] = new Circle(radius, center);
myCircle[thisPosition]->PrintCircle();
thisPosition++;
break;
case 2: // For printing a particular cirle from the list of cirles
cout << " Enter the Value for which Circle to Print: ";
cin >> printPosition;
myCircle[printPosition - 1]->PrintCircle();
break;
case 3: // For printing all the circles in the class object array pointer list
cout << "\n";
for (int i = 0; i < thisPosition; i++){
myCircle[i]->PrintCircle();
cout << "\n==============================" << endl;
}
break;
case 4:
cout << "\n Good Bye !!! \n " << endl;
break;
}
cout << "\nHere's the menu of choices: ";
cout << "\n1. Add a Circle.\n";
cout << "2. Print a Circle. \n";
cout << "3. Print all Cricles \n";
cout << "4. Exit.";
cout << "Please enter your choice: ";
cin >> choice;
system("pause");
}
}

Answer 1

You could also use a std::vector<std::function<void()>> choices(5);... and call it like choices[choice](); after you filled it with the alternative choices like choices[1] = &function_1; etc...
But I have a feeling the real question is not really about how to avoid switch...
[EDIT]
Based on your comment, I think the question is how to avoid duplicating the "menu" output. Simply refactor like this using a do..while:
cout << " *********************Intensive Program 1***********************\n\n" << endl;
cout << "\nHere's the menu of choices: ";
cout << "\n1. Add a Circle.\n";
cout << "2. Print a Circle. \n";
cout << "3. Print all Cricles \n";
cout << "4. Exit.\n";
cout << "\nPlease enter your choice: ";
do
{
cin >> choice;
switch (choice){
case 1:
// For adding cirles to the class
cout << " Enter the value for the radius of the circle: ";
cin >> radius;
cout << " Enter the value for the center of the circle: ";
cin >> center;
myCircle[thisPosition] = new Circle(radius, center);
myCircle[thisPosition]->PrintCircle();
thisPosition++;
break;
case 2: // For printing a particular cirle from the list of cirles
cout << " Enter the Value for which Circle to Print: ";
cin >> printPosition;
myCircle[printPosition - 1]->PrintCircle();
break;
case 3: // For printing all the circles in the class object array pointer list
cout << "\n";
for (int i = 0; i < thisPosition; i++){
myCircle[i]->PrintCircle();
cout << "\n==============================" << endl;
}
break;
case 4:
cout << "\n Good Bye !!! \n " << endl;
break;
}
system("pause");
}
} while(choice != 4);
If you still want the menu to be repeated for each choice, then simply cut and paste the menu printing at the start of the do..while loop.
As a side note, I strongly suggest you read https://mikeash.com/getting_answers.html for the next time.

Answer 2

Using if-else ladder is one of the alternatives for switch statements.
cout << " *********************Intensive Program 1***********************\n\n" << endl;
cout << "\nHere's the menu of choices: ";
cout << "\n1. Add a Circle.\n";
cout << "2. Print a Circle. \n";
cout << "3. Print all Cricles \n";
cout << "4. Exit.\n";
cout << "\nPlease enter your choice: ";
cin >> choice;
while (choice <4){
if(choice==1)
{
// For adding cirles to the class
cout << " Enter the value for the radius of the circle: ";
cin >> radius;
cout << " Enter the value for the center of the circle: ";
cin >> center;
myCircle[thisPosition] = new Circle(radius, center);
myCircle[thisPosition]->PrintCircle();
thisPosition++;
}
else if(choice==2)
{ // For printing a particular cirle from the list of cirles
cout << " Enter the Value for which Circle to Print: ";
cin >> printPosition;
myCircle[printPosition - 1]->PrintCircle();
}
else if(choice==3) // For printing all the circles in the class object array pointer list
{
cout << "\n";
for (int i = 0; i < thisPosition; i++){
myCircle[i]->PrintCircle();
cout << "\n==============================" << endl;
}
}
else
{
cout << "\n Good Bye !!! \n " << endl;
}
}
system("pause");
}