📅  最后修改于: 2023-12-03 15:21:57.743000             🧑  作者: Mango
在进行链表操作时,我们有时需要删除一些节点,本文将介绍如何从循环单向链表中删除所有偶数和节点。
以下是 JavaScript 语言的示例代码片段,用于从循环单向链表中删除所有偶数和节点。
function deleteEvenNodes(head) {
let current = head;
let prev = null;
let count = 0;
while (current && current.next !== head) {
if (current.data % 2 === 0) {
// If node to be deleted is head node
if (current === head) {
// Find the last node in the list
let temp = head;
while (temp.next !== head) {
temp = temp.next;
}
// Point last node to next of head
temp.next = head.next;
head = temp.next;
} else {
// Node to be deleted is non-head node
prev.next = current.next;
}
// Update current pointer
current = prev.next;
count++;
} else {
// Node is not even, update previous pointer
prev = current;
// Move the current pointer
current = current.next;
}
}
// Handle head node separately
if (current && current.next === head && current.data % 2 === 0) {
// If only 1 node exists in the list
if (current === head) {
head = null;
} else {
// If node to be deleted is tail node
prev.next = current.next;
}
count++;
}
console.log(`Total nodes deleted: ${count}`);
return head;
}
该算法的时间复杂度为 $O(N)$。
本算法并不需要对链表进行排序。
我们可以编写一些单元测试来测试该算法的正确性,以保证它能够正确完成从循环单向链表中删除所有偶数和节点的任务。