From 9c1737f0bfaf4727406ea59ab0acc7bfef25a5f2 Mon Sep 17 00:00:00 2001 From: markilue <745518019@qq.com> Date: Thu, 22 Dec 2022 12:39:18 +0800 Subject: [PATCH] =?UTF-8?q?leecode=E6=9B=B4=E6=96=B0?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...inarySearch.java => T01_BinarySearch.java} | 2 +- ...oveElement.java => T02_RemoveElement.java} | 2 +- ...bArrayLen.java => T03_MinSubArrayLen.java} | 2 +- ...ateMatrix.java => T04_generateMatrix.java} | 2 +- .../leecode/array/T05_SortedSquares.java | 105 ++++++++++++++++++ .../array/second/T01_BinarySearch.java | 65 +++++++++++ .../leecode/listnode/ListNodeUtils.java | 57 ++++++++++ 7 files changed, 231 insertions(+), 4 deletions(-) rename Leecode/src/main/java/com/markilue/leecode/array/{BinarySearch.java => T01_BinarySearch.java} (98%) rename Leecode/src/main/java/com/markilue/leecode/array/{RemoveElement.java => T02_RemoveElement.java} (98%) rename Leecode/src/main/java/com/markilue/leecode/array/{MinSubArrayLen.java => T03_MinSubArrayLen.java} (98%) rename Leecode/src/main/java/com/markilue/leecode/array/{generateMatrix.java => T04_generateMatrix.java} (97%) create mode 100644 Leecode/src/main/java/com/markilue/leecode/array/T05_SortedSquares.java create mode 100644 Leecode/src/main/java/com/markilue/leecode/array/second/T01_BinarySearch.java create mode 100644 Leecode/src/main/java/com/markilue/leecode/listnode/ListNodeUtils.java diff --git a/Leecode/src/main/java/com/markilue/leecode/array/BinarySearch.java b/Leecode/src/main/java/com/markilue/leecode/array/T01_BinarySearch.java similarity index 98% rename from Leecode/src/main/java/com/markilue/leecode/array/BinarySearch.java rename to Leecode/src/main/java/com/markilue/leecode/array/T01_BinarySearch.java index 277a04c..c25f4ef 100644 --- a/Leecode/src/main/java/com/markilue/leecode/array/BinarySearch.java +++ b/Leecode/src/main/java/com/markilue/leecode/array/T01_BinarySearch.java @@ -5,7 +5,7 @@ package com.markilue.leecode.array; * 描述:给定一个n个元素有序的（升序）整型数组nums 和一个目标值target ，写一个函数搜索nums中的 target，如果目标值存在返回下标，否则返回 -1。 * */ -public class BinarySearch { +public class T01_BinarySearch { public static void main(String[] args) { int[] nums = {-1,0,3,5,9,12}; diff --git a/Leecode/src/main/java/com/markilue/leecode/array/RemoveElement.java b/Leecode/src/main/java/com/markilue/leecode/array/T02_RemoveElement.java similarity index 98% rename from Leecode/src/main/java/com/markilue/leecode/array/RemoveElement.java rename to Leecode/src/main/java/com/markilue/leecode/array/T02_RemoveElement.java index eb6cdc8..9a1e2b4 100644 --- a/Leecode/src/main/java/com/markilue/leecode/array/RemoveElement.java +++ b/Leecode/src/main/java/com/markilue/leecode/array/T02_RemoveElement.java @@ -11,7 +11,7 @@ import java.util.Arrays; * 不要使用额外的数组空间，你必须仅使用 O(1) 额外空间并 原地 修改输入数组。 * 元素的顺序可以改变。你不需要考虑数组中超出新长度后面的元素。 */ -public class RemoveElement { +public class T02_RemoveElement { @Test diff --git a/Leecode/src/main/java/com/markilue/leecode/array/MinSubArrayLen.java b/Leecode/src/main/java/com/markilue/leecode/array/T03_MinSubArrayLen.java similarity index 98% rename from Leecode/src/main/java/com/markilue/leecode/array/MinSubArrayLen.java rename to Leecode/src/main/java/com/markilue/leecode/array/T03_MinSubArrayLen.java index 65daa65..edc9fbb 100644 --- a/Leecode/src/main/java/com/markilue/leecode/array/MinSubArrayLen.java +++ b/Leecode/src/main/java/com/markilue/leecode/array/T03_MinSubArrayLen.java @@ -7,7 +7,7 @@ import javax.management.remote.rmi._RMIConnection_Stub; /** * 寻找长度最小的子数组 */ -public class MinSubArrayLen { +public class T03_MinSubArrayLen { @Test diff --git a/Leecode/src/main/java/com/markilue/leecode/array/generateMatrix.java b/Leecode/src/main/java/com/markilue/leecode/array/T04_generateMatrix.java similarity index 97% rename from Leecode/src/main/java/com/markilue/leecode/array/generateMatrix.java rename to Leecode/src/main/java/com/markilue/leecode/array/T04_generateMatrix.java index ada702b..35eee09 100644 --- a/Leecode/src/main/java/com/markilue/leecode/array/generateMatrix.java +++ b/Leecode/src/main/java/com/markilue/leecode/array/T04_generateMatrix.java @@ -8,7 +8,7 @@ import java.util.Arrays; * 螺旋矩阵: * 给你一个正整数 n ，生成一个包含 1 到 n2 所有元素，且元素按顺时针顺序螺旋排列的 n x n 正方形矩阵 matrix */ -public class generateMatrix { +public class T04_generateMatrix { @Test diff --git a/Leecode/src/main/java/com/markilue/leecode/array/T05_SortedSquares.java b/Leecode/src/main/java/com/markilue/leecode/array/T05_SortedSquares.java new file mode 100644 index 0000000..c4f9b88 --- /dev/null +++ b/Leecode/src/main/java/com/markilue/leecode/array/T05_SortedSquares.java @@ -0,0 +1,105 @@ +package com.markilue.leecode.array; + +import org.junit.Test; + +import java.util.Arrays; + +/** + *@BelongsProject: Leecode + *@BelongsPackage: com.markilue.leecode.array + *@Author: dingjiawen + *@CreateTime: 2022-12-22 11:02 + *@Description: + * TODO 力扣977题 有序数组的平方: + * 给你一个按 非递减顺序 排序的整数数组 nums，返回 每个数字的平方 组成的新数组，要求也按 非递减顺序 排序。 + *@Version: 1.0 + */ +public class T05_SortedSquares { + @Test + public void test(){ + int[] nums = {-4, -1, 0, 3, 10}; + System.out.println(Arrays.toString(sortedSquares(nums))); + } + + @Test + public void test1(){ + int[] nums = {-7,-3,2,3,11}; + System.out.println(Arrays.toString(sortedSquares1(nums))); + } + + @Test + public void test2(){ + int[] nums = {-10000,-3,2,3,10000}; + System.out.println(Arrays.toString(sortedSquares(nums))); + } + + /** + * 思路:先找到最接近0的数，然后左右比较进行遍历 + * 时间复杂度应该在O(N),空间复杂度也是O(N) + * 速度击败100%，内存击败43.93% + * @param nums + * @return + */ + public int[] sortedSquares(int[] nums) { + //寻找第一个大于0的数 + int targetIndex = 0; + for (int i = 0; i < nums.length; i++) { + if (nums[i] <= 0) targetIndex++; + } + //在第一个大于0的数旁边左右遍历 + int left = targetIndex - 1; + int index = 0; + int[] result = new int[nums.length]; + while (left >= 0 && targetIndex <= nums.length - 1) { + if(-nums[left]>nums[targetIndex]){ + result[index++]=nums[targetIndex]*nums[targetIndex]; + targetIndex++; + }else { + result[index++]=nums[left]*nums[left]; + left--; + } + } + //后面的用完了 + while (left>=0){ + result[index++]=nums[left]*nums[left]; + left--; + } + //前面的用完了 + while (targetIndex<= nums.length - 1){ + result[index++]=nums[targetIndex]*nums[targetIndex]; + targetIndex++; + } + + return result; + + + } + + + /** + * 代码随想录思路:虽然最小的数不知道，但最大的数一定是在数组的两边产生；避免找0的过程 + * 时间复杂度在O(N),空间复杂度也是O(N) + * 速度击败100%，内存击败63.68% + * @param nums + * @return + */ + public int[] sortedSquares1(int[] nums) { + + //从两边开始双向奔赴遍历，两边的最大值一定是最大值 + int right=nums.length-1; + int left = 0; + int index = nums.length-1; + int[] result = new int[nums.length]; + while (left <=right) { + if(-nums[left]>nums[right]){ + result[index--]=nums[left]*nums[left]; + left++; + }else { + result[index--]=nums[right]*nums[right]; + right--; + } + } + + return result; + } +} diff --git a/Leecode/src/main/java/com/markilue/leecode/array/second/T01_BinarySearch.java b/Leecode/src/main/java/com/markilue/leecode/array/second/T01_BinarySearch.java new file mode 100644 index 0000000..c857c20 --- /dev/null +++ b/Leecode/src/main/java/com/markilue/leecode/array/second/T01_BinarySearch.java @@ -0,0 +1,65 @@ +package com.markilue.leecode.array.second; + +/** + * 二刷 + * 力扣题号704：二分查找 + * 描述:给定一个n个元素有序的（升序）整型数组nums 和一个目标值target ，写一个函数搜索nums中的 target，如果目标值存在返回下标，否则返回 -1。 + * + */ +public class T01_BinarySearch { + + public static void main(String[] args) { + int[] nums = {-1,0,3,5,9,12}; + int target = 9; + + System.out.println(search(nums,target)); + } + + + /** + * 非递归法 + * @param nums + * @param target + * @return + */ + public static int search(int[] nums, int target) { + + int left=0; + int right=nums.length-1; + + while (left<=right){ + int mid=left+((right-left)>>1); + + if(nums[mid]target){ + right=mid-1; + }else { + return mid; + } + } + //出来了还没找到 + return -1; + + + + } + + + /** + * 递归法 + * @param nums + * @param target + * @return + */ + public static int search1(int[] nums, int target) { + + return 0; + } + + public static int find(int[] nums,int start,int stop, int target){ + + + return 0; + } +} diff --git a/Leecode/src/main/java/com/markilue/leecode/listnode/ListNodeUtils.java b/Leecode/src/main/java/com/markilue/leecode/listnode/ListNodeUtils.java new file mode 100644 index 0000000..4c9cf52 --- /dev/null +++ b/Leecode/src/main/java/com/markilue/leecode/listnode/ListNodeUtils.java @@ -0,0 +1,57 @@ +package com.markilue.leecode.listnode; + +import org.junit.Test; + +import java.util.List; + +/** + *@BelongsProject: Leecode + *@BelongsPackage: com.markilue.leecode.listnode + *@Author: dingjiawen + *@CreateTime: 2022-12-22 11:55 + *@Description: TODO 链表的使用工具 + *@Version: 1.0 + */ +public class ListNodeUtils { + + @Test + public void testPrint(){ + int[] nodeList= {2, 4, 3}; + ListNode root = build(nodeList); + print(root); +// print(); + } + + /** + * 通过一个val数组建立链表 + * @param nodeList + * @return + */ + public static ListNode build(int[] nodeList){ + ListNode root =new ListNode(nodeList[0]); + ListNode temp=root; + for (int i = 1; i < nodeList.length; i++) { + temp.next= new ListNode(nodeList[i]); + temp=temp.next; + } + return root; + } + + /** + * 打印链表 + * @param root + */ + public static void print(ListNode root){ + StringBuilder builder=new StringBuilder("["); + ListNode temp=root; + while (temp!=null){ + builder.append(temp.val); + builder.append(","); + temp=temp.next; + } + builder.append("]"); + + System.out.println(builder.toString()); + + } +}