//radix sort method for link list. (click here to go link list)

void List::radixSort(){
    //find max;
    Node *max = FirstItem;
    Node *temp = FirstItem;

    while( temp != NULL){
        if(temp->data > max->data ){
            max = temp;
        }
        temp = temp->next
    }

    //convert int to string
    string s;
    std::stringstream out;
    out << max->data;
    s = out.str();

    int digit = s.length();
    List a[10];    

    int divider;
    int tempi;

    for(int i = 0; i < digit; i++){
        temp = FirstItem;
        while(temp != NULL){
            divider = pow(10.0,(double)i);
            tempi = (temp->data / divider) % 10
            a[tempi].AddListItem(temp->data)
            temp = temp->next;
        }
        deletion();
        for(int i = 0; i < 10; i++)
            while(a[i].FirstItem != NULL){
                AddListItem(a[i].FirstItem->data);
                a[i].FirstItem = (a[i].FirstItem)->next;
            }
        }
    }
}