01. Write a CPP program to find the sum of Individual digits of a Positive Integer

#include<iostream.h>

int sumofdigits(int);            //function declaration

int main()
{
    int n,sod;
    cout<<"Please enter a valid +ve Integer"<<endl;
    cin>>n;                          //reading Integer
    while(n<0)                     //validating Integer
    {
        cout<<"You have entered a -ve Number"<<endl;
        cout<<"Please enter a valid +ve Integer"<<endl;
        cin>>n;
    }
    sod=sumofdigits(n);        //function calling
    cout<<"Sum of digits of given Integer is :"<<sod;
    return 0;
}

int sumofdigits(int n)            //called function
{
    int sod=0;                       //initializing variable
    while(n!=0)
    {
        sod=sod+n%10;
        n=n/10;
    }
    return sod;
}