删除有序链表中的重复元素,使链表中的所有元素都只出现一次
例如:
给出的链表为1->1->2,返回1->2.
给出的链表为1->1->2->3->3,返回1->2->3.
<?php
class Node {
public $next = null;
public $val;
public function __construct($val) {
$this->val = $val;
}
}
function deleteDuplicates($head) {
$node = $head;
while ($node != null) {
if ($node->val == $node->next->val) {
$node->next = $node->next->next;
} else {
$node = $node->next;
}
}
return $head;
}
$node1 = new Node(1);
$node2 = new Node(2);
$node3 = new Node(3);
$node4 = new Node(3);
$node1->next = $node2;
$node2->next = $node3;
$node3->next = $node4;
$ret = deleteDuplicates($node1);
while ($ret != null) {
print $ret->val . "\n";
$ret = $ret->next;
}