Question

a. Write a c++ function called IsPalindrome that receives a 3-digit number and returns whether it is palindrome or not. [2.5 marks]

b. Write a c++ function, called GCD that receives two parameters n, d, and prints their greatest common divisor [2.5 marks]

1. Now after you created the two functions, you have to write a main function that can call the above functions according to user choice. Write a menu that allows the user to select from the following options [5 marks]

1. To use the IsPalindrome function you have to enter 1.
2. To use the GCD function you have to enter 2.
3. To Exit the program you have to enter 3. [use exit(0)]

Once the user select one of the above choices you have to read the value entered by the user and then to call the respective function.

Answer 1

#include <iostream>

using namespace std;

//function to find if number is palindrome 
int IsPalindrome()
{
    int p;
    do{
        cout<<"Enter a three digit number: ";
        cin>>p;
    }while(p>999 ||p<100);
    if(p%10==p/100)     //if first and last digit(of 3 digit number) are same then it is palindrome
    {
        cout<<"The number is palindrome\n";
        return 1;        //return 1 if it is palindrome
    }
    else
    {
        cout<<"The number is not palindrome\n";
        return 0;           //returning 0 if it is not palindrome
    }
    
}

// function to find gcd
void GCD(int n, int d)
{
    int gcd;
    for(int i=1; i <= n && i <= d; ++i)
    {
        // Checks if i is factor of both integers
        if(n%i==0 && d%i==0)
            gcd = i;
    }
    //printing gcd of both numbers
    cout<<"The gcd of numbers "<<n<<" and "<<d<<" is: "<<gcd<<endl;
}

//function to display menu
void menu()
{
    cout<<"Enter 1 to use find palindrome: \n";
    cout<<"Enter 2 to use find GCD: \n";
    cout<<"Enter 3 to use find Exit: \n";
}
int main()
{
    int choice,n,d,p;
    // loop to ask user for his/her choice
    while (1)
    {
        menu();       //calling menu function
        cin>>choice;          //taking input foe choice
        switch (choice)
                {
                case 1:       //if user chosses 1
                    IsPalindrome();   //calling palindrome function
                        break;
                case 2:   //if user chooses 2 
                        cout << "Enter two numbers: ";       //asking for input for gcd function
                        cin >> n >> d;           //taking input from user
                        GCD(n,d);           //calling function
                        break;
                case 3:          //if user enters 3
                        exit(0);   
                        break;
        default:         //if user enters invalid input
                        cout << "Invalid input" << endl;
        }

    }
    return 0;
}

ss for reference: