#include<bits/stdc++.h>
using namespace std;
void print(int arr[],int length){
    for (int i =0;i<length;i++)
        cout <<arr[i] <<" ";
    cout << endl;
}
void swap(int *a, int *b){
    int temp = *a;
    *a = *b;
    *b = temp;
}
int partition(int arr[], int start, int end){
    int pIndex = start;
    for(int i = start;i<end;i++){
        if(arr[i]<arr[end]){
            swap(&arr[i],&arr[pIndex]);
            pIndex++;
        }
    }
    swap(&arr[pIndex], &arr[end]);
    return pIndex;
}
void quicksort(int arr[],int start, int end){
    if (start>=end) return;
    int pIndex = partition(arr,start,end);
    quicksort(arr,start,pIndex-1);
    quicksort(arr,pIndex+1,end);
}
void findPair(int arr[], int length, int key){
    quicksort(arr,0,length-1);
    //print(arr,length);
    int i =0,j=1;
    while(i<length && j<length){
        if(abs(arr[i] - arr[j]) == key){
            cout<< arr[i] <<" "<<arr[j] << endl;
            i++;j++;
        }
        else if (abs(arr[i] - arr[j]) < key) j++;
        else i++;
    }
}
int main(){
    int arr[] = {4,2,5,8,21,34,10}, key =24, length = sizeof(arr)/sizeof(arr[0]);
    findPair(arr,length,key);

    return 0;
}