nest if statements

How can i write the same code using a nested if statement instead of a series of if statements?

/* Reads a positive single digit integer and prints the word equivalent for it.
for example. 5 = five. */
#include<stdio.h>
void main()
{
int a, keep=1;
while(keep>=0)
{
printf("\nEnter a single digit: ");
scanf("%d",&a);
if(a==0)
printf("You have entered zero");
if(a==1)
printf("You have entered one");
if(a==2)
printf("You have entered two");
if(a==3)
printf("You have entered three");
if(a==4)
printf("You have entered four");
if(a==5)
printf("You have entered five");
if(a==6)
printf("You have entered six");
if(a==7)
printf("You have entered seven");
if(a==8)
printf("You have entered eight");
if(a==9)
printf("You have entered nine");
printf("\nEnter a positive number to continue or a negative number to terminate ");
scanf("%d",&keep);
}
printf("\nTerminating");
}

Use the switch statement:

Code:

---

switch(a)
{
  case 0: printf("You have entered zero"); break;
  case 1: printf("You have entered one"); break;
  ...
}

---

or use else if:

Code:

---

if(a==0)
  printf("You have entered zero");
else if(a==1)
  printf("You have entered one");
else if(a==2)
  printf("You have entered two");
...

---

Or use an array:

Code:

---

char *digits[] = { "zero", "one", "two", "three", "four",
                  "five", "six", "seven", "eight", "nine" };

...

if(a >= 0 && a < (sizeof(digits)/sizeof(*digits)))
  printf("You have entered %s\n", digits[a]);

---

If you are doing what Monster is doing, you could use enum.

u cannot use a nested if statement for whatever u want to do.
a nested if stucture is something like

Code:

---

if(cond1)
{
if(cond2)
{
if(cond3)
{
...and so on....
}
}
}

---

so what u r doing i snot possible using nested if. i think all the other ways possible (other than what u have done) have been explained by Monster.

Quote:

---

Originally Posted by gooddevil

u cannot use a nested if statement for whatever u want to do.

---

Yes you can.

Code:

---

printf("You entered ");
if( a > -1 )
{
    if( a > 0 )
    {
        if( a > 1 )
        {
            if( a > 2 )
            {
                ...and so on...
            }
            else
            {
                printf("two");
            }
        }
        else
        {
            printf("one");
        }
    }
    else
    {
        printf("zero");
    }
}
else
{
    printf("an invalid number");
}
printf(".\n");

---

:)

Quzah.

yes i am sorry, my fault. i din think it that way.thanx for corrections

a nested if style uses just as much code as clover's.
i would use monster's array method.

Quote:

---

Originally Posted by sand_man

a nested if style uses just as much code as clover's.
i would use monster's array method.

---

Actually, it uses more due to the else statements. It wasn't a question of if it was a better way; it was an an answer showing that it could be done. The poster just prior to that stated it couldn't be done. I was illustrating that it can indeed be done.

Additionally, if this were a homework requirement, which it may well have been, due to the way the first post was worded, the exercise may require they use nested if statements.

Quzah.