Perfect number

If a positive integer is equal to the sum of all divisors except itself , Call it a perfect number .
Perfect number

for(int i = 1; i < 1000; i++)
{
int sum = 0;
for(int j = 1; j < i; j++)
{
if (i % j == 0)
{
sum += j;
}
}
if (sum == i)
{
Console.WriteLine(i);
}

Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp3
{
    
    class Program
    {
    
        static void Main(string[] args)
        {
    
            for(int i = 1; i < 1000; i++)
            {
    
                int sum = 0;
                for(int j = 1; j < i; j++)
                {
    
                    if (i % j == 0)
                    {
    
                        sum += j;
                    }
                 }
                if (sum == i)
                {
    
                    Console.WriteLine(i);
                }
               
            }
            Console.ReadKey();
        }
    }
}

result

Previous perfect numbers within 6 28 496

Output all Narcissus

The number of daffodils is a three digit number , The cube sum of its digits is equal to the number itself
daffodils

int a, b, c;
for(int i = 100; i < 1000; i++)
{
a = i / 100;
b = i / 10 %10;
c = i % 10;
if (a * a * a + b * b * b + c * c * c == i)
{
Console.WriteLine(i);
}

Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp4
{
    
    class Program
    {
    
        static void Main(string[] args)
        {
    
            int a, b, c;
            for(int i = 100; i < 1000; i++)
            {
    
                a = i / 100;
                b = i / 10 %10;
                c = i % 10;
                if (a * a * a + b * b * b + c * c * c == i)
                {
    
                    Console.WriteLine(i);
                }
            }
            Console.ReadKey();
        }
    }
}

result

The number of daffodils is 153 370 371 407

The use of the class

Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp6
{
    
    class Student
    {
    
        public string name;
        public string sex;
        public int age;
        public Student(string name, string sex)
        {
    

        }
        public Student(string name, string sex,int age)
        {
    
            this.name = name;
            this.sex = sex;
            this.age = age;

        }
        public void Inderduce()
        {
    
            Console.WriteLine(" My name is "+this.name+" I am a "+this.sex+" Child , I this year "+this.age+" year ");

        }
    }
    class Program
    {
    
        static void Main(string[] args)
        {
    
            Student s1 = new Student(" Xiaohua "," male ",20);
            Student s2 = new Student(" floret "," Woman ",18);
            s1.Inderduce();
            s2.Inderduce();
            Console.ReadKey();

        }
    }
}

Output results