Write a menu driven Program which has following options: 1. Factorial of a number. 2. Prime or not. 3. Odd or even 4. Exit Once a menu item is selected the appropriate action should be taken and once this action is finished, the menu should reappear. Unless the user selects the ‘Exit’ option the program should continue to work

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/*Program to find factorial of a number, the number is prime or not ,the number is odd or even,exit

Author: Knowledge desk , Date: Decmber10,2020*/

#include<stdio.h>

#include<conio.h>

main()

  {

     int num;

     printf("Enter 1 to find factorial of a number.");

     printf("Enter 2 to find number is prime or not.");

     printf("Enter 3 to find number is odd or even.");

     printf("Enter 4 to exit.");

     clrscr();

     printf("Enter a value :");

     scanf("%d",&num);

     switch(num)

{

   case 1:

      printf("\nYou enter 1 to find the factorial of a number");

      // Program to find factorial of a number //

      {

int n,i,fact=1;

printf("\nEnter an integer:");

scanf("%d",&n);

if(n < 0)

    {

       printf("\nfactorial of anegative number does not exist.");

    }

else

    {

       for(i=1;i<=n;i++)

  {

     fact *= i;

  }

       printf("\nThe factorial for %d =%11u",n,fact);

    }

      }

      break;

   case 2:

      printf("\nYou enter 2 to find the number is prime or not");

      // Program to find the number is prime or not//

      {

int num,count = 0, i;

printf("\nEnter a digit to find the prime number :");

scanf("%d",&num);

for(i=2;i<=num/2;i++)

    {

       if(num%i==0)

  {

     count++;

  }

    }

if (count == 0)

    {

       printf("\n\nThe number is prime %d.",num);

    }

else

    {

       printf("\n\nThe number is not prime %d.",num);

    }

      }

      break;

   case 3:

      printf("\nYou enter 3 to find odd or even.");

      // Program to find odd or even //

      {

int num;

printf("\nEnter a number to find odd or even :");

scanf("%d",&num);

if(num%2==0)

    {

       printf("\nThe number is even.%d",num);

    }

else

    {

       printf("\nThe number is not even.%d",num);

    }

      }

      break;

   case 4:

      printf("\n You enter 4 to exit ");

      exit(0);

      break;

   default :

      printf("\n Please enter a valid number");

}

     getch();

     return(0);

  }