text: function plus(){
  
      var counter=1;
      var sum=0;
      var a = parseInt(document.getElementById("final").value);
      var sum = a+counter;
      document.getElementById("final").value = sum;
  
  }
  
  
  function minus(){
  
      var counter=1;
      var sum=0;
      var a = parseInt(document.getElementById("final").value);
      var sum = a-counter;
      document.getElementById("final").value = sum;
  
  }
  
  