Given an array A[] and a number x, check for pair in A[] with sum as x

given an array A[] of n numbers and another number x, determines whether or not there exist two elements in S whose sum is exactly x.

Code:

package microsoftInterviewPrep;

import java.util.Arrays;

public class KeyPair {
   
    static void findKeyPair(int[] a, int sum){
       
        Arrays.sort(a);
       
        int l = 0;
        int r = a.length -1;
       
        while(l < r){
           
            int currsum = a[l]+ a[r];
           
            if(currsum == sum){
                System.out.println("The pairs with sum "+ sum+" are: "+ a[l]+" and "+a[r]);
                break;
            }
            else if( currsum < sum){
                l++;
            }
            else{
                r--;
            }
        }
       
       
    }
   
   
   
    public static void main(String[] args){
       
          int a[] = {1, 4, 45, 6, 10, -8};
          int n = 16;
          findKeyPair(a, n);
       
       
    }

}


Output:

The pairs with sum 16 are: 6 and 10


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