Perfect Number
A Perfect Number is a positive integer that is equal to the sum of factors i.e. the sum of its positive factors excluding the number itself.
Example - Factors of 6 : 1,2,3
Input : 6
Sum of Factors : 1 + 2 + 3 = 6
Output : It is a Perfect Number
Factors of 28 : 1,2,4,7,14
Input : 28
Sum of Factors : 1 + 2 + 4 + 7 + 14 = 28
Output : It is a Perfect Number
Algorithm and Program below :-
Algorithm :-
Get the number to check for Perfect Number
Hold the number in temporary variable
Store the sum of its factors excluding the number itself
Compare the sum of factors with the number
If both are equal print "Perfect Number"
If not print "Not a Perfect Number"
Program :-
import java.io.*; import java.util.*; class Perfect { public static void main(String args[]) { Scanner in= new Scanner(System.in); int n,p,s=0,i; System.out.println("Enter No."); n= in.nextInt(); // Input number from user p=n; // store the entered number in "p" variable for(i=1;i<n;i++) // loop to find the factors { if(n%i==0) // Cpndition for factors of number { s=s+i; // storing sum of factors excluding number } } if(s==p) //comparing sum of factors with number { System.out.println("It is a Perfect Number : "+p); } else { System.out.println("It is not a Perfect Number : "+p); } } // end of main method } // end of class
Note : The program is written in the easiest way possible so try understand it. If you face any problem in understanding this program than feel free to contact/comment.
All the Best :)
Keep Learning :)
Comments