Display the sum of a number's digits.

//Program to display the sum of a number's digits.
#include<iostream.h>
#include<conio.h>
void main()
{
    clrscr();
    int a,b,c;
    cout<<"Enter a number to display sum of it's digits: ";
    cin>>a;
    b=a%10;
    while(a!=0)
    {
        a=a/10;
        c=a%10;
        b=b+c;
    }
    cout<<"The sum of the digits is: "<<b;
    getch();
}