ex5

#include <iostream>
#include <cmath>
using namespace std;

int main()
{//problema 5
 unsigned long n,d,S;
 cout<<"n=";cin>>n;
   //a
   S=1+n;;
  for (d=2;d<=sqrt(n);d++)
    if (n%d==0)
  {
      S+=d;
      if (n/d>d)
      S+=n/d;
  }
  cout<<"Suma="<<S<<endl; //suma tuturor div sai
  //b
  S-=n;
  if (S==n)
    cout<<"nr e perfect";
  else
    cout<<"nr nu e perfect";

return 0;
}