#include <bits/stdc++.h>
#define NULL 0
using namespace std;
struct Node{
    int data1,data2,data3;
    Node* next;
};
Node *head = NULL;
int min_diff = INT_MAX;
Node* insert(int data1, int data2, int data3){
    Node* temp = new Node();
    temp->data1 = data1;
    temp->data2 = data2;
    temp->data3 = data3;
    temp->next = NULL;
    if(head == NULL){
        head = temp;
        return head;
    }else{
        temp->next = head;
        head = temp;
        return head;
    }
}

void print(){
    Node *temp = head;
    while(temp != NULL){
        cout << temp->data1 <<" "<< temp->data2<<" "<<temp->data3<<endl;
        temp = temp->next;
    }
}
void make_sub_array(int arr[], int length){
    int diff;
    for(int i =0;i<length; i++){
        for(int j =i+1;j<length;j++){
            diff = abs(arr[i] - arr[j]);
            insert(arr[j],arr[i],diff);
            min_diff = min_diff>diff?diff:min_diff;
        }
    }
}
void small_sub(){
    Node *temp=head;
    //int min = temp->data3 ;
    while(temp!=NULL){
        if(temp->data3 == min_diff) cout << "("<<temp->data1<<","<<temp->data2<<") ";
        temp=temp->next ;
    }
}
int main()
{
      int arr[] = {5,4,3,2,1};
      make_sub_array(arr,sizeof(arr)/sizeof(arr[0]));
      small_sub();
    return 0;
}