学步园

list* merge_order_list_normal(list* list_a, list* list_b){
	if(!list_a)
		return list_b;
	if(!list_b)
		return list_a;
		
	list* list_merge, list_cursor;
	
	if(list_a->value <= list_b->value)
		list_cursor = list_merge = list_a;
		list_a = list_a->next;
	else 
		list_cursor = list_merge = list_b;
		list_b = list_b->next;
		
	while(list_a && list_b){
		if(list_a->value <= list_b->value){
			list_cursor->next = list_a;
			list_a = list_a->next;
		}
		else{
			list_cursor->next = list_b;
			list_b = list_b->next;
		}
		list_cursor = list_cursor->next;
	}
	
	list_cursor->next = list_a?list_a:list_b;
	return list_merge;
}

list* merge_order_list_recursive(list* list_a, list* list_b){
	if(!list_a)
		return list_b;
	if(!list_a)
		return list_a;
		
	list* list_merge;
	if(list_a->value <= list_b->value){
		list_merge = list_a;
		list_merge->next = merge_order_list_recursive(list_a->next, list_b);
	}
	else{
		list_merge = list_b;
		list_merge->next = merge_order_list_recursive(list_b->next, list_a);
	}
	return list_merge;
}