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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright [yyyy] [name of copyright owner] + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. diff --git a/README.md b/README.md deleted file mode 100644 index 0192cb0..0000000 --- a/README.md +++ /dev/null @@ -1,4 +0,0 @@ -## 2021-11-29 -- java 基础练习 -- 剑指offer -- leetcode \ No newline at end of file diff --git a/src/com/datastructures/wangdao/linearlist/linklist/LinkList.java b/src/com/datastructures/wangdao/linearlist/linklist/LinkList.java deleted file mode 100644 index 196260f..0000000 --- a/src/com/datastructures/wangdao/linearlist/linklist/LinkList.java +++ /dev/null @@ -1,97 +0,0 @@ -package com.datastructures.wangdao.linearlist.linklist; - -import com.leetcode.common.ListNode; - -import java.util.Scanner; - -public class LinkList { - /** - * lc206反转链表:头插法建立链表 - * T(n) = O(n), S(n) = O(1) - */ - public ListNode reverseList(ListNode head) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0); - while (head != null) { - // next是临时缓存指针，保证链表不断链 - ListNode next = head.next; - head.next = dummy.next; - dummy.next = head; - head = next; - } - return dummy.next; - } - - /** - * 尾插法建立链表，和输入顺序一致 - * T(n) = O(n), S(n) = O(1) - */ - public ListNode createList(int[] array) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0), tail = dummy; - for (int a : array) { - ListNode s = new ListNode(a); - tail.next = s; - tail = s; - } - return dummy.next; - } - - /** - * 在链表head的第i个节点前插入一个元素e，假设链表长度为n, i范围是[0,n] - * T(n) = O(n), S(n) = O(1) - */ - public ListNode insert(ListNode head, int i, int e) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0); - dummy.next = head; - ListNode p = head; - // 计算表长 - int n = 0; - while (p != null) { - p = p.next; - n++; - } - - p = dummy; - int j = 0; - if (i < 0 || i > n) { - return dummy.next; - } - // 查找第i-1个节点 - while (p != null && j < i) { - p = p.next; - j++; - } - // 插入元素 - if (p != null) { - ListNode s = new ListNode(e); - s.next = p.next; - p.next = s; - } - return dummy.next; - } - - /** - * 删除链表中第一个为val的节点 - * T(n) = O(n), S(n) = O(1) - */ - public ListNode deleteElement(ListNode head, int val) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0); - dummy.next = head; - // 双指针遍历 - ListNode pre = dummy, p = pre.next; - // 查找 - while (p != null && p.val != val) { - pre = p; - p = p.next; - } - // 删除 - if (p != null) { - pre.next = p.next; - } - return dummy.next; - } - -} diff --git a/src/com/java/se/chapter1/access/mytest_demo/A.java b/src/com/java/se/chapter1/access/mytest_demo/A.java deleted file mode 100644 index 6360cd8..0000000 --- a/src/com/java/se/chapter1/access/mytest_demo/A.java +++ /dev/null @@ -1,6 +0,0 @@ -package com.java.se.chapter1.access.mytest_demo; - -public class A { - protected void fun(){ - } -} diff --git a/src/com/java/se/chapter1/access/test_demo/B.java b/src/com/java/se/chapter1/access/test_demo/B.java deleted file mode 100644 index 2ac0f22..0000000 --- a/src/com/java/se/chapter1/access/test_demo/B.java +++ /dev/null @@ -1,11 +0,0 @@ -package com.java.se.chapter1.access.test_demo; - -import com.java.se.chapter1.access.mytest_demo.A; - -public class B extends A { - public void test() { - this.fun(); - super.fun(); -// new A().fun();//编译异常，没有访问权限 - } -} diff --git a/src/com/leetcode/Solution0001.java b/src/com/leetcode/Solution0001.java deleted file mode 100644 index 99d24aa..0000000 --- a/src/com/leetcode/Solution0001.java +++ /dev/null @@ -1,25 +0,0 @@ -package com.leetcode; - -import java.util.HashMap; -import java.util.Map; - -/** - * T(n)=O(n*log n) - * S(n)=O(n) - */ -public class Solution0001 { - public int[] twoSum(int[] nums, int target) { - int[] result = new int[2]; - Map map = new HashMap<>(); - - for (int i = 0; i < nums.length; i++) { - if (map.containsKey(target - nums[i])) { - result[1] = i; - result[0] = map.get(target - nums[i]); - return result; - } - map.put(nums[i], i); - } - return result; - } -} diff --git a/src/com/leetcode/Solution0002.java b/src/com/leetcode/Solution0002.java deleted file mode 100644 index a78efed..0000000 --- a/src/com/leetcode/Solution0002.java +++ /dev/null @@ -1,49 +0,0 @@ -package com.leetcode; - -import com.leetcode.common.ListNode; - -/** - * T(n)=O(max(m,n)) - * S(n)=O(1) - */ -public class Solution0002 { - public ListNode addTwoNumbers(ListNode l1, ListNode l2) { - ListNode l = new ListNode(); - ListNode p = l; - int add = 0; - while (true) { - if (l1 != null && l2 != null) { - ListNode r = new ListNode(); - r.val = (l1.val + l2.val + add)%10; - add = (l1.val + l2.val + add)/10; - l1 = l1.next; - l2 = l2.next; - p.next = r; - p = r; - } else if (l1 != null) { - ListNode r = new ListNode(); - r.val = (l1.val + add)%10; - add = (l1.val + add)/10; - l1 = l1.next; - p.next = r; - p = r; - } else if (l2 != null) { - ListNode r = new ListNode(); - r.val = (l2.val + add)%10; - add = (l2.val + add)/10; - l2 = l2.next; - p.next = r; - p = r; - } else if (add != 0){ - ListNode r = new ListNode(); - r.val = add; - add = 0; - p.next = r; - p = r; - } else { - break; - } - } - return l.next; - } -} diff --git a/src/com/leetcode/Solution0003.java b/src/com/leetcode/Solution0003.java deleted file mode 100644 index 599ebaa..0000000 --- a/src/com/leetcode/Solution0003.java +++ /dev/null @@ -1,25 +0,0 @@ -package com.leetcode; - -import java.util.HashMap; - -/** - * 不重复子串最大长度 - * 1、变长滑动窗口，若想返回最后一个最长不重复子串，只需在更新maxLen时存储j、i，最终subString即可 - * 2、T(n) = O(n), S(n) = O(log(n)) - */ -public class Solution0003 { - public int lengthOfLongestSubstring(String s) { - int n = s.length(); - if (n==0) return 0; - HashMap map = new HashMap();//map存String不重复字符的较大索引 - int maxLen=0; - for (int i=0, j=0; ii遍历指针 - if (map.containsKey(s.charAt(i))){//如果存在相同元素 - j = Math.max(j,map.get(s.charAt(i))+1);//j相同字符下一个元素下标 - } - map.put(s.charAt(i),i); - maxLen = Math.max(maxLen,i-j+1);//更新最大长度，i-j+1代表当前窗口 - } - return maxLen; - } -} diff --git a/src/com/leetcode/Solution0074.java b/src/com/leetcode/Solution0074.java deleted file mode 100644 index c7b6c29..0000000 --- a/src/com/leetcode/Solution0074.java +++ /dev/null @@ -1,23 +0,0 @@ -package com.leetcode; - -/** - * 最简单杨氏矩阵，二分查找思想 - */ -public class Solution0074 { - public boolean searchMatrix(int[][] matrix, int target) { - if (matrix == null || matrix.length == 0 || matrix[0].length == 0) { - return false; - } - int i = 0, j = matrix[0].length-1; - while (i < matrix.length && j >=0) { - if (target > matrix[i][j]) { - i++; - } else if (target < matrix[i][j]) { - j--; - } else { - return true; - } - } - return false; - } -} diff --git a/src/com/leetcode/Solution0203.java b/src/com/leetcode/Solution0203.java deleted file mode 100644 index 911d7b6..0000000 --- a/src/com/leetcode/Solution0203.java +++ /dev/null @@ -1,29 +0,0 @@ -package com.leetcode; - -import com.leetcode.common.ListNode; - -public class Solution0203 { - public ListNode removeElements(ListNode head, int val) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0); - dummy.next = head; - // 双指针遍历 - ListNode pre = dummy, p = pre.next; - boolean found = false; - // 查找并删除 - while (p != null) { - if (p.val == val) { - pre.next = p.next; - found = true; - } - // 查找并删除结点后只移动p，pre不移动,found需重置 - if (!found) { - pre = p; - } else { - found = false; - } - p = p.next; - } - return dummy.next; - } -} diff --git a/src/com/leetcode/common/ListNode.java b/src/com/leetcode/common/ListNode.java deleted file mode 100644 index 38eb2db..0000000 --- a/src/com/leetcode/common/ListNode.java +++ /dev/null @@ -1,12 +0,0 @@ -package com.leetcode.common; - -// 单/双链表结点，单链表节点时不care prev 即可 -public class ListNode { - public int val; - public ListNode next; - public ListNode prev; - public ListNode() {} - public ListNode(int val) { this.val = val; } - public ListNode(int val, ListNode next) { this.val = val; this.next = next;} - public ListNode(int val, ListNode next, ListNode prev) { this.val = val; this.next = next; this.prev = prev;} -} diff --git a/src/com/leetcode/linkedlist/MergeList/Solution0021.java b/src/com/leetcode/linkedlist/MergeList/Solution0021.java deleted file mode 100644 index 314a672..0000000 --- a/src/com/leetcode/linkedlist/MergeList/Solution0021.java +++ /dev/null @@ -1,31 +0,0 @@ -package com.leetcode.linkedlist.MergeList; - -import com.leetcode.common.ListNode; - -/** - * 合并两个有序链表为有序链表：尾插法建立返回值链表 - * T(n) = O(m+n), S(n) = O(1) - */ -public class Solution0021 { - public ListNode mergeTwoLists(ListNode list1, ListNode list2) { - ListNode l = new ListNode(), tail = l; // 建立一个头结点，统一每个节点的操作 - while (list1 != null && list2 != null) { - if (list1.val >= list2.val) { - tail.next = list2; - tail = list2; - list2 = list2.next; - } else { - tail.next = list1; - tail = list1; - list1 = list1.next; - } - } - if (list1 != null) { - tail.next = list1; - } - if (list2 != null) { - tail.next = list2; - } - return l.next; - } -} diff --git a/src/com/leetcode/linkedlist/MergeList/Solution0088.java b/src/com/leetcode/linkedlist/MergeList/Solution0088.java deleted file mode 100644 index 33f6f91..0000000 --- a/src/com/leetcode/linkedlist/MergeList/Solution0088.java +++ /dev/null @@ -1,22 +0,0 @@ -package com.leetcode.linkedlist.MergeList; - -/** - * 合并2个升序数组的变体 - * T(n) = O(m+n), S(n) = O(1) - */ -public class Solution0088 { - public void merge(int[] nums1, int m, int[] nums2, int n) { - int i = m-1, j = n-1, k=m+n-1; - while (i>=0 && j >=0) { - if (nums1[i] <= nums2[j]) { - nums1[k--] = nums2[j--]; - } else { - nums1[k--] = nums1[i--]; - } - } - while (j>=0) { - // num2还没遍历完事 - nums1[k--] = nums2[j--]; - } - } -} diff --git a/src/com/leetcode/linkedlist/MyLinkedList.java b/src/com/leetcode/linkedlist/MyLinkedList.java deleted file mode 100644 index 97459c4..0000000 --- a/src/com/leetcode/linkedlist/MyLinkedList.java +++ /dev/null @@ -1,194 +0,0 @@ -package com.leetcode.linkedlist; - -import com.leetcode.common.ListNode; - -/** - * lc701 设计链表：单链表方式 - */ -public class MyLinkedList { - /** - * 虚拟头结点 - */ - private ListNode dummy; - - public MyLinkedList() { - dummy = new ListNode(0, null); - } - public ListNode dummy() { - return dummy; - } - public int size() { - int size = 0; - ListNode cur = dummy.next; - while (cur != null) { - ++size; - cur = cur.next; - } - return size; - } - - public int get(int index) { - if (index < 0) { - return -1; - } - int i = 0; - ListNode cur = dummy.next; - while (cur != null && i < index) { - i++; - cur = cur.next; - } - return cur == null ? -1:cur.val; - } - - public void addAtHead(int val) { - ListNode s = new ListNode(val); - s.next = dummy.next; - dummy.next = s; - } - - public void addAtTail(int val) { - ListNode s = new ListNode(val); - ListNode cur = dummy.next; - ListNode tail = dummy; - while (cur != null) { - tail = cur; - cur = cur.next; - } - tail.next = s; - } - - public void addAtIndex(int index, int val) { - ListNode cur = dummy; - int i = 0; - // 查找第index-1个节点 - while (cur != null && i < index) { - cur = cur.next; - i++; - } - // 插入元素 - if (cur != null) { - ListNode s = new ListNode(val); - s.next = cur.next; - cur.next = s; - } - } - - public void deleteAtIndex(int index) { - if (index < 0) { - return; - } - ListNode cur = dummy; - int i = 0; - // 查找第index-1个节点 - while (cur != null && i < index) { - cur = cur.next; - i++; - } - if (cur != null && cur.next != null) { - cur.next = cur.next.next; - } - } -} - - - - -///** -// * lc701 设计链表：双链表方式 -// */ -//public class MyLinkedList { -// /** -// * 虚拟头结点 -// */ -// private ListNode dummy; -// -// public MyLinkedList() { -// dummy = new ListNode(0, null, null); -// } -// public ListNode dummy() { -// return dummy; -// } -// public int size() { -// int size = 0; -// ListNode cur = dummy.next; -// while (cur != null) { -// ++size; -// cur = cur.next; -// } -// return size; -// } -// -// public int get(int index) { -// if (index < 0) { -// return -1; -// } -// int i = 0; -// ListNode cur = dummy.next; -// while (cur != null && i < index) { -// i++; -// cur = cur.next; -// } -// return cur == null ? -1:cur.val; -// } -// -// public void addAtHead(int val) { -// ListNode s = new ListNode(val); -// s.next = dummy.next; -// if (dummy.next != null) { -// dummy.next.prev = s; -// } -// dummy.next = s; -// s.prev = dummy; -// } -// -// public void addAtTail(int val) { -// ListNode s = new ListNode(val); -// ListNode cur = dummy.next; -// ListNode tail = dummy; -// while (cur != null) { -// tail = cur; -// cur = cur.next; -// } -// tail.next = s; -// s.prev = tail; -// } -// -// public void addAtIndex(int index, int val) { -// ListNode cur = dummy; -// int i = 0; -// // 查找第index-1个节点 -// while (cur != null && i < index) { -// cur = cur.next; -// i++; -// } -// // 插入元素 -// if (cur != null) { -// ListNode s = new ListNode(val); -// s.next = cur.next; -// if (cur.next != null) { -// cur.next.prev = s; -// } -// cur.next = s; -// s.prev= cur; -// } -// } -// -// public void deleteAtIndex(int index) { -// if (index < 0) { -// return; -// } -// ListNode cur = dummy; -// int i = 0; -// // 查找第index-1个节点 -// while (cur != null && i < index) { -// cur = cur.next; -// i++; -// } -// if (cur != null && cur.next != null) { -// if (cur.next.next != null) { -// cur.next.next.prev = cur; -// } -// cur.next = cur.next.next; -// } -// } -//} \ No newline at end of file diff --git a/src/com/leetcode/linkedlist/Solution0206.java b/src/com/leetcode/linkedlist/Solution0206.java deleted file mode 100644 index 85379ef..0000000 --- a/src/com/leetcode/linkedlist/Solution0206.java +++ /dev/null @@ -1,38 +0,0 @@ -package com.leetcode.linkedlist; - -import com.leetcode.common.ListNode; - - -public class Solution0206 { - /** - * 反转链表:头插法建立链表 - * T(n) = O(n), S(n) = O(1) - */ - public ListNode reverseList(ListNode head) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0); - while (head != null) { - // next是临时缓存指针，保证链表不断链 - ListNode next = head.next; - head.next = dummy.next; - dummy.next = head; - head = next; - } - return dummy.next; - } - - /** - * 尾插法建立链表，和输入顺序一致 - * T(n) = O(n), S(n) = O(1) - */ - public ListNode createList(int[] array) { - // 建立一个 dummy 虚拟节点，方便统一操作 - ListNode dummy = new ListNode(0), tail = dummy; - for (int a : array) { - ListNode s = new ListNode(a); - tail.next = s; - tail = s; - } - return dummy.next; - } -} diff --git a/src/com/sword2offer/Hello.java b/src/com/sword2offer/Hello.java deleted file mode 100644 index 36324f3..0000000 --- a/src/com/sword2offer/Hello.java +++ /dev/null @@ -1,4 +0,0 @@ -package com.sword2offer; - -public class Hello { -}