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 Exit option the program should continue to run.
[Hint: Make use of infinite loop and a switch statement. ]
#include<stdio.h>
#include<conio.h>
int main()
{
int a,x,num,p,fact,prm;
for(a=2;a>1;a++)
{
printf("\n\nEnter what your choice.\n");
printf("\n\n1. Find factorial.");
printf("\n\n2. Check Prime number.");
printf("\n\n3. Check even and odd.\n\n4. Exit.\n");
scanf("%d", &x);
switch(x)
{
case(1):
printf("Enter the number of what you want to find the factorial :");
scanf("%d", &num);
fact=num;
for(p=1;p<num;p++)
fact=fact*p;
printf("%d is the factorial.", fact);
break;
case(2):
printf("Enter the number which you want to check whether it is prime or not : ");
scanf("%d", &num);
for(;p<num;p++)
{
prm=num%p;
if(prm==0)
{
printf("%d is not a prime number.", num);
break;
}
if(p==num-1)
printf("%d is a prime number.", num);
}
break;
case(3):
printf("Enter the number to check whether it is even or odd : ");
scanf("%d", &num);
if(num%2==0)
printf("%d is an even number.", num);
else
printf("%d is odd odd number.", num);
break;
}
if(x==4)
{
printf("\n\nOk Thank you for using this program.\n\n Bye.\n\n Exiting.");
break;
}
if(x!=1 && x!=2 && x!=3 && x!=4)
printf("You have entered the wrong choice. Try Again!!");
}
getch();
return 0;
}