Page 571 - ComputerScience_Class_11

Program 5 Define a class Smith to check whether a number is a Smith number or not.

Eg: A Smith number is a composite number, the sum of whose digits is the sum of the digits
of its prime factors obtained as a result of prime factorisation (excluding 1). The first few
such numbers are 4, 22, 27, 58, 85, 94, 121, …
Example:
N = 666
Prime factors are 2, 3, 3, 37
Sum of the digits = 6 + 6 + 6 = 18
Sum of the digits of the factors 2 + 3 + 3 + 3 + 7 = 18
Hence, 666 is a Smith Number.
The data members and the member methods are defined as follows:

int n : To store the number
Member Methods
boolean composite(int x) : To check whether a number is composite or not
int sum_of_digits(int x) : To find the sum of the digits of a number
int sum_prime(int x) : To find the sum of the prime factors of the number
Also, write the main method to call the function.

1 import java.util.*;
2 class Smith
3 {

4 int n;
5 //Member methods

6 boolean composite(int n)
7 {

8 int flag = 0,i;
9 for(i = 1; i <= n; i++)

10 if(n % i == 0)
11 flag++;

12 if(flag > 2)
13 return true;

14 return false;
15 }

16 int sum_of_digits(int n)
17 {

18 int s = 0,i=n;
19 while(i!=0)

20 {

Internal Assessment 569