Help me in solving MISSP problem

help
,
1

My issue

why my code is showing error could you please explain

My code

import java.util.*;
import java.lang.*;
import java.io.*;

class Codechef
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner sc=new Scanner(System.in);
		int t=sc.nextInt();
		for(int p=0;p<t;p++){
		    int n=sc.nextInt();
		    Map<Integer,Integer> count=new HashMap<>();
		    for(int i=0;i<n;i++){
		        int temp=sc.nextInt();
		        count.put(temp,count.getOrDefault(temp,0)+1);
		    }
		    for(Map.Entry<Integer,Integer> e:count.entrySet()){
		        if(e.getValue()==1){
		            System.out.println(e.getKey());
		            break;
		        }
		    }
		    
		}

	}
}

Learning course: Arrays, Strings & Sorting
Problem Link: Chef and Dolls Practice Problem in Arrays, Strings & Sorting - CodeChef

2

@klu_2200032721
the simpler logic will be the xor of the whole array.