C – Find Sum of Digits till Single Digit

C Program to find Sum of Digits till Single Digit:

9657 -> 9+6+5+7 -> 27 -> 2+7 -> 9

int main() {             int num, sum, dig;             printf(“Enter num : “);             scanf(“%d”, &num);             printf(“%d-> “,num);             while(num/10!=0)             {                         sum = 0;                         while(num!=0)                         {                                     dig=num%10;                                     sum+=dig;                                     num/=10;                                }                         printf(“%d->”, sum);                         num=sum;             } }