## Introduction

I have used CodeBlocks compiler for debugging purpose. But you can use any C++ programming language compiler as per your availability.

#include <iostream> using namespace std; // Function declarations int isPerfect(int num); void printPerfect(int start, int end); int main() { int start, end; // Inputting lower and upper limit to print perfect numbers cout<<"Enter lower limit to print perfect numbers: "; cin>>start; cout<<"Enter upper limit to print perfect numbers: "; cin>>end; cout<<"All perfect numbers between "<<start<< " to "<<end <<" are: "<<endl; printPerfect(start, end); return 0; } int isPerfect(int num) { int i, sum; // Finding sum of all proper divisors sum = 0; for(i=1; i<num; i++) { if(num % i == 0) { sum += i; } } /* If sum of proper positive divisors equals to given number then the number is perfect number */ if(sum == num) return 1; else return 0; } //Printing all perfect numbers void printPerfect(int start, int end) { // Iterating from start to end while(start <= end) { if(isPerfect(start)) { cout<<start<<endl; } start++; } }