我正在尝试将2-3-4树转换为java中的红黑树,但我很难搞清楚它.
我写了这两个基本类如下,以使问题简单明了,但无法弄清楚从哪里开始.
public class TwoThreeFour<K> {
public List<K> keys;
public List<TwoThreeFour<K>> children;
}
public class RedBlack<K> {
public K key;
public boolean isBlack;
public RedBlack<K> left,right;
public RedBlack<K key, boolean isBlack, RedBlack<K> left, RedBlack<K> right){
this.key = key; this.isBlack = isBlack; this.left = left; this.right = right;
}
}
我假设2-3-4树是有效的,并且想要在调用方法时返回一个红黑树.
我也试过以下代码而没有运气:
public convert(TwoThreeFour<K> tTF){
if (ttf.keys.size() == 3)
RedBlack<K> node = RedBlack<ttf.keys[1], true, RedBlack<ttf.keys[0], false, /* not sure what to put here for left */, /* not sure what to …我正试图在lisp中遍历一棵树并打印出所有父子关系.这是我的输入:(5(3(4(1))(g)(9(6)))(n(8(0))(q)(7)(b(f(c(a))) )))我试图让它打印出以下内容:
5>3
5>n
3>4
3>g
3>9
4>1
9>6
n>8
n>q
n>7
n>b
8>0
b>f
f>c
c>a
我目前的代码如下:
(defun par-child-print (l)
(print l)
(cond ((not (null (caadr l)))
(print "start")
(print (car l))
(print ">")
(print (caadr l))
(print "end")
(cond ((not (atom (car l))) (when (not (eq (car l) NIL)) (par-child-print (car l)))));
(when (not (eq (cdr l) NIL)) (par-child-print (cdr l)))
)
(t
)));
问题是我的输出有时只打印父级(并且它不会通过整个树).有任何想法吗？
我也有这个通过整个树,但甚至没有试图跟踪父母:
(defun atom-print (l)
(print l)
(cond ((atom l) (print l));
(t
(when …