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]);