功能是输出1到1000内能被它整除的数加起来的和为它本身的，如6=1+2+3，而且1,2,3也能被6整除public class Perfect
{
    public static void main(String []perfect)
    {
        int i,j,num=0;
        for(i=3;i<=1000;i++)
        {
            for(j=1;j<=Math.sqrt(1000);j++)
            {
                if(i%j==0&&i!=j)
                {
                    num+=j;
                }
            }
            if(num==i)
            {
                System.out.println(" "+i);
            }
        }
    }
}