//ex2: Pair of numbers: sum of divisor = another number
#include<stdio.h>
#include<stdlib.h>
int inputArray(int arr[], int size);
int sumOfDivisors(int num);
void pairOfNumbers(int arr[], int size);
int main(){
int arr[50], size;
size = inputArray(arr, size);
pairOfNumbers(arr, size);
return 0;
}
int inputArray(int arr[], int size){
printf("Enter size of Array: ");
scanf("%d", &size);
for(int i = 0; i < size; i++){
printf("arr[%d] = ", i);
scanf("%d", &arr[i]);
return size;
int sumOfDivisors(int num){
int sum = 0;
for(int i = 1; i <= num; i++){
if(num % i == 0){
sum += i;
return sum;
void pairOfNumbers(int arr[], int size){
printf("Pair of numbers: sum of divisor = another number\n");
for(int j = i + 1; j < size; j++){
if(sumOfDivisors(arr[i]) == arr[j]){
printf("Sum of divisors of arr[%d] (%d) = arr[%d] (%d)\n", i, arr[i], j, arr[j]);