g0501_0600.s0507_perfect_number.Solution Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of leetcode-in-java Show documentation

Java-based LeetCode algorithm problem solutions, regularly updated

There is a newer version: 1.39

package g0501_0600.s0507_perfect_number;

// #Easy #Math #2022_03_19_Time_2_ms_(73.73%)_Space_41.4_MB_(11.81%)

public class Solution {
    public boolean checkPerfectNumber(int num) {
        int s = 1;
        for (int sq = (int) Math.sqrt(num); sq > 1; sq--) {
            if (num % sq == 0) {
                s += sq + (num / sq);
            }
        }
        return num != 1 && s == num;
    }
}