#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
int s=1,c=1,a[10],n,i,m=0;
a[0]=1;
cout<<"\nenter a no. to check for a perfect no.";
cin>>n;
for(i=2;i<=n;i++)
{
if(n%i==0)
{
c=c*i;
a[s]=i;
s++;
if(c==n)
{
for(i=0;i<s;i++)
{
m=m+a[i];
}
if(m==n)
cout<<"\nit is a perfect no.";
else
cout<<"\nnot a perfect no.";
}
}
}
getch();
}