java programme to add number lesser than hundred

package ahmed;

import java.util.Scanner;

public class ahmed {

		
		static Scanner a = new Scanner(System.in);
		
	    public static void main(String[] args)
	    {
	   
	    
	 int sum=0 ; 
	 int counter=0;
	 
	  while(counter<4) {
		  
		  
		  System.out.println("Enter your number to add");
		  int asd = a.nextInt();
		  
		  if(asd>100 || asd<0) {
			  
			  System.out.println("invaild , enter new number");
			  continue;
			  
		  }
		  sum +=asd;
		  counter++;
		  
	  }System.out.println("your number is " + sum);
	    	
	    	
	    	
	    	
	     }    	
	    	
	    }
	

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