Description
Get the input from the user and check whether that number is a perfect number or not.
E.g. Let number is 28, factors of 28 are 1,2,4,7,14. Now the sum of all these factors are 28 itself.
Input
28
Output
Perfect Number
Input
4
Output
Not a perfect number
C Program
Method 1
#include <stdio.h>
int main()
{
int i,num,sum=0;
printf("Enter a number: ");
scanf("%d",&num);
for(i=1;i<num;i++)
{
if(num%i==0)
sum=sum+i;
}
if(num==sum)
printf("Perfect number");
else
printf("Not a perfect number");
return 0;
}
Method 2
#include <stdio.h>
#include<math.h>
int main()
{
int i,num,sum=0;
printf("Enter a number: ");
scanf("%d",&num);
for(i=1;i<=sqrt(num);i++)
{
if (num%i==0)
{
if(i==1)
sum=sum+i;
else if(i==num/i)
sum=sum+i;
else
sum=sum+i+num/i;
}
}
if(num==sum)
printf("Perfect number");
else
printf("Not a perfect number");
return 0;
}
C++ Program
Method 1
#include <iostream>
using namespace std;
int main()
{
int i,num,sum=0;
cout<<"Enter a number: ";
cin>>num;
for(i=1;i<num;i++)
{
if(num%i==0)
sum=sum+i;
}
if(num==sum)
cout<<"Perfect number";
else
cout<<"Not a perfect number";
return 0;
}
Method 2
#include <iostream>
#include<math.h>
using namespace std;
int main()
{
int i,num,sum=0;
cout<<"Enter a number: ";
cin>>num;
for(i=1;i<=sqrt(num);i++)
{
if (num%i==0)
{
if(i==1)
sum=sum+i;
else if(i==num/i)
sum=sum+i;
else
sum=sum+i+num/i;
}
}
if(num==sum)
cout<<"Perfect number";
else
cout<<"Not a perfect number";
return 0;
}
Java
import java.util.Scanner;
public class Main
{
public static void main(String[] args) {
Scanner sc=new Scanner(System.in);
System.out.print("Enter a number: ");
int num=sc.nextInt();
int sum=0;
for(int i=1;i<num;i++)
{
if(num%i==0)
sum=sum+i;
}
if(sum==num)
System.out.println("Perfect Number");
else
System.out.println("Not an Perfect Number");
}
}
Python
num=int(input("Enter a number: "))
Sum=0
for i in range(1,num):
if num%i==0:
Sum=Sum+i
if(Sum==num):
print("Perfect Number")
else:
print("Not a perfect number")
