/* function sum_num(){  
    var total = 0;  
    for(var i=0;i<arguments .length;i++){  
        total+=arguments[i];  
    }  
    return total;  
}  

alert(sum_num(2,34,45,56,56)); */

 function sum_num(){  
    var total = 0;  
    for(var i=0;i<arguments .length;i++){  
        total+=arguments[i];  
    }  
     alert(sum_num(total)); 
}  

sum_num();

求大神解答呀？