function zliczaj_znaki(my_form)  
 {  
 if(my_form.tresc_op.value.length<=2000)  
 {  
 a=my_form.tresc_op.value.length;  
 b=2000;  
 c=b-a;  
 document.getElementById('ile').innerHTML= '('+c+')';  
 }  
 else  
 {  
 my_form.tresc_op.value = my_form.tresc_op.value.substring(0, 2000);  
 }}