Answer to Question #40439 in C++ for Ahmed al mamari

Question

Make use of switch statement. The outline of this program is given below:
/* A menu driven program */
void main
{
int choice ;
int Number;
while (1)
{
printf ( "\n1. Factorial" ) ;
printf ( "\n2. Odd/Even" ) ;
printf ( "\n3. Exit" ) ;\
printf("\n Enter Number");
scanf("%d",&Number);
printf ( "\nYour choice? " ) ;
scanf ( "%d", &choice ) ;
switch ( choice )
{
case 1 :
/* logic for factorial of a Number */
break ;
case 2 :
/* logic for odd/even */
break ;
case 3 :
exit() ;
}
}
}

Answer 1

#include <stdio.h>
#include <stdbool.h>

int factorial(long long int n) {
if ( n < 0 ) {
return -1;
}
if ( n < 2 ) {
return 1;
} else {
return n * factorial(n-1);
}
}

bool even(int n) {
if ( n % 2 == 0 ) {
return true;
}
return false;
}

int main() {
int choice ;
int Number;

while (1) {
printf ( "\n1. Factorial" ) ;
printf ( "\n2. Odd/Even" ) ;
printf ( "\n3. Exit" ) ;\
printf("\nEnter Number\n");
scanf("%d",&Number);
printf ( "\nYour choice?\n" ) ;
scanf ( "%d", &choice ) ;
switch ( choice ) {
case 1 :
printf(" Factorial of the number %d is %d", Number, factorial(Number));
break ;
case 2 :
if ( even(Number) == true ) {
printf("The given number is even\n");
} else {
printf("The number is odd\n");
}
break ;
case 3 :
return 0 ;
default:
printf("Please do the choice correctly\n");
break;
}
}
return 0;
}