A - Yet Another Dividing into Teams

import java.util.Arrays;
import java.util.Scanner;


public class NewClass {
    

    public static void main(String[] args) {
         //int cnt=1;
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        
       
        while(x-->0){
          int  t = sc.nextInt();
            boolean conflicto = false;
             int[] arr = new int[t];
            for(int i = 0;i<arr.length;i++){
                arr[i] = sc.nextInt();
            }
           Arrays.sort(arr);
            for(int i = 0;i<arr.length-1 && !conflicto ;i++){
               
                    if((arr[i]-arr[i+1]) == -1 ){
                        conflicto = true;
                        //continue;
                        
                    }}
                    if(conflicto){
				System.out.println("2");
			}
			else{
				System.out.println("1");
			}
                } 
            
     

                            }
           
        }