Perfect Number between 1 and 1000

Question

I try to find the perfect number between 1 and 1000, i wrote this code but it didn't work! what is wrong?

public class Perfect {
    public static void main(String[]args) {
        int sum=0;
        for (int n = 1; n < 1000; n++) {
            for (int j = 1; j < n/2 ; j++) {
                if (n % j == 0)
                    sum = sum + j;
            }
            if (sum == n) {
                System.out.println(sum);
            }
        }
    }
}

You never reset the value of `sum`, so at each iteration it starts with its previous value. — yshavit, Dec 24 '15 at 17:08

Elliott Frisch · Accepted Answer · 2015-12-24T17:17:40.850

0

Move the declaration (and more importantly the initialization) of sum into the for loop. Also, you need to test <= in the inner loop. Something like,

for (int n = 1; n < 1000; n++) {
  int sum = 0;
  for (int j = 1; j <= n / 2; j++) {

And I get 496.

edited Dec 24 '15 at 17:17

answered Dec 24 '15 at 17:08

Elliott Frisch

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@DavidWallace Thanks. Edited. – Elliott Frisch Dec 24 '15 at 17:17
1

Actually, you get 6, 28 AND 496. – Dawood ibn Kareem Dec 24 '15 at 17:19

Perfect Number between 1 and 1000

1 Answers1