Program to Print the entered number into words

The following C program print’s the entered number in words. For example if the number entered is 12345 then the program prints the entered number in words as One Two Three Four Five

#include<stdio.h>
void main()
{
int i=0;
unsigned long int digit;
char str[12],ch;
puts(“Enter the number (less than 10 digit)”);
scanf(“%lu”,&digit);
ultoa(digit,str,10); /*converts an unsigned long int to string*/
while(str[i]!=’?)
{
ch=str[i];
i++;
switch(ch)
{
case ’1?:
printf(“ONE “);
break;
case ’2?:
printf(“TWO “);
break;
case ’3?:
printf(“THREE “);
break;
case ’4?:
printf(“FOUR “);
break;
case ’5?:
printf(“FIVE “);
break;
case ’6?:
printf(“SIX “);
break;
case ’7?:
printf(“SEVEN “);
break;
case ’8?:
printf(“EIGHT “);
break;
case ’9?:
printf(“NINE “);
break;
case ’0?:
printf(“ZERO “);
break;
}
}
}