Find_Pair_Given_Difference.java

// { Driver Code Starts
//Initial Template for Java
import java.io.*;
import java.util.*;

class GfG {
  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);
    int t = sc.nextInt();

    while (t-- > 0) {
      int l = sc.nextInt();
      int n = sc.nextInt();

      int arr[] = new int[l];

      for (int i = 0; i < l; i++)
        arr[i] = sc.nextInt();

      Solution ob = new Solution();

      if (ob.findPair(arr, l, n) == true)
        System.out.println(1);

      else
        System.out.println(-1);

    }

  }
}

class Solution {
  public boolean findPair(int arr[], int size, int n) {
    Arrays.sort(arr);
    for (int i = 0; i < size; i++) {
      int diff = 0;
      if (n > arr[i])
        diff = n + arr[i];
      if (n <= arr[i])
        diff = arr[i] - n;
      if (Arrays.binarySearch(arr, diff) > -1)
        return true;
    }
    return false;
  }
}