01 #include<stdio.h>
02 
03 int main()
04  {
05   int n,num,x,sum=0; 
06   printf("Enter a number=");
07   scanf("%d",&n); 
08 
09   while(n>0) 
10   {
11    x=n%10; 
12    sum=sum+x; 
13    n=n/10; 
14   }
15  printf("Sum of digits of a number=%d",sum); 
16  
17  return 0;
18 }

 
 OUTPUT :
 
 Enter a number : 123
 
 Sum of digits of a number : 6