Recursive function For counting all the perfect number from 1 to n.
What is a perfect number? A perfect number is a positive integer that is equal to the sum of its positive divisors , excluding the number itself. For instance, 6 has divisors 1, 2 and 3 (excluding itself), and 1 + 2 + 3 = 6, so 6 is a perfect number. C program to count all perfect numbers from 1to N. #include"stdio.h" int perfect(int num) { /* function to check number is perfect or not*/ if(num<1) { return 0; } int i, sum, n; sum = 0; n = num; for(i=1; i<n; i++) { /* If i is a divisor of num */ if(n%i == 0) { sum += i; } } if(num==sum) { printf("number is %d\n",num); ...