leecode更新

Leecode/src/main/java/com/markilue/leecode/hot100/T75_MoveZeroes.java

@@ -0,0 +1,107 @@
+package com.markilue.leecode.hot100;
+
+import org.junit.Test;
+
+import java.util.Arrays;
+
+/**
+ *@BelongsProject: Leecode
+ *@BelongsPackage: com.markilue.leecode.hot100
+ *@Author: markilue
+ *@CreateTime: 2023-03-19  11:05
+ *@Description:
+ * TODO  力扣283题  移动零:
+ *   给定一个数组 nums，编写一个函数将所有 0 移动到数组的末尾，同时保持非零元素的相对顺序。
+ *   请注意 ，必须在不复制数组的情况下原地对数组进行操作。
+ *@Version: 1.0
+ */
+public class T75_MoveZeroes {
+
+    @Test
+    public void test() {
+        int[] nums = {0, 1, 0, 3, 12};
+        moveZeroes1(nums);
+        System.out.println(Arrays.toString(nums));
+    }
+
+    @Test
+    public void test1() {
+        int[] nums = {1, 0, 1};
+        moveZeroes(nums);
+        System.out.println(Arrays.toString(nums));
+    }
+
+
+    /**
+     * 思路:双指针
+     * 速度击败32.68%  内存击败25.8%  2ms
+     * @param nums
+     */
+    public void moveZeroes(int[] nums) {
+
+        int left = 0;//找零的
+        int right = 0;//找不是零的
+
+        while (left < nums.length && right < nums.length) {
+            while (left < nums.length && nums[left] != 0) {
+                left++;
+            }
+
+            while (right < nums.length && nums[right] == 0) {
+                right++;
+            }
+
+            if (right < nums.length && left < right) {
+                swap(nums, left, right);
+            } else if (left > right) {
+                right = left + 1;
+            }
+
+        }
+
+    }
+
+    public void swap(int[] nums, int left, int right) {
+        int temp = nums[left];
+        nums[left] = nums[right];
+        nums[right] = temp;
+    }
+
+
+    /**
+     * 官方解答:
+     * 速度击败32.68%  内存击败72.91%  2ms
+     * @param nums
+     */
+    public void moveZeroes1(int[] nums) {
+        int n = nums.length, left = 0, right = 0;
+        while (right < n) {
+            if (nums[right] != 0) {
+                swap(nums, left, right);
+                left++;
+            }
+            right++;
+        }
+    }
+
+
+    /**
+     * 官方最快:直接赋值，不用交换
+     * 速度击败100%  内存击败24.58%  1ms
+     * @param nums
+     */
+    public void moveZeroes2(int[] nums) {
+        int index=0;
+        for (int i = 0; i < nums.length; i++) {
+            if(nums[i]!=0){
+                nums[index++]=nums[i];
+            }
+
+        }
+        //index后面的全是0
+        for (int i =index; i <nums.length ; i++) {
+            nums[i]=0;
+        }
+    }
+
+}

Leecode/src/main/java/com/markilue/leecode/hot100/T76_FindDuplicate.java

@@ -0,0 +1,100 @@
+package com.markilue.leecode.hot100;
+
+import org.junit.Test;
+
+/**
+ *@BelongsProject: Leecode
+ *@BelongsPackage: com.markilue.leecode.hot100
+ *@Author: markilue
+ *@CreateTime: 2023-03-19  11:32
+ *@Description:
+ * TODO  力扣287  寻找重复数:
+ *   给定一个包含 n + 1 个整数的数组 nums ，其数字都在 [1, n] 范围内（包括 1 和 n），可知至少存在一个重复的整数。
+ *   假设 nums 只有 一个重复的整数 ，返回 这个重复的数 。
+ *   你设计的解决方案必须 不修改 数组 nums 且只用常量级 O(1) 的额外空间。
+ *@Version: 1.0
+ */
+public class T76_FindDuplicate {
+
+    @Test
+    public void test() {
+        int[] nums = {1, 3, 4, 2, 2};
+        System.out.println(findDuplicate2(nums));
+    }
+
+    /**
+     * 因为数字都在1-n之间，所以总和是一定的
+     * 使用总和减去现在的总和，就可以知道差值
+     * 不对:一个整数不是一定出现两次，可能出现多次
+     * @param nums
+     * @return
+     */
+    public int findDuplicate(int[] nums) {
+
+        int totalSum = 0;
+        int curSum = 0;
+        for (int i = 0; i < nums.length; i++) {
+            totalSum += (i + 1);
+            curSum += nums[i];
+        }
+
+        return nums.length - (totalSum - curSum);
+
+    }
+
+
+    /**
+     * 官方二分查找法:注意这里是mid,不是nums[mid]，奇特的地方就在于，如果一个数有重复的数的话，那么小于这个数的count一定>它本身
+     * 时间复杂度O(nlogn)
+     * 速度击败15.73%  内存击败39.73%  28ms
+     * @param nums
+     * @return
+     */
+    public int findDuplicate1(int[] nums) {
+
+        int n = nums.length;
+        int l = 1, r = n - 1, ans = -1;
+        while (l <= r) {
+            int mid = (l + r) >> 1;
+            int cnt = 0;
+            for (int i = 0; i < n; ++i) {
+                if (nums[i] <= mid) {
+                    cnt++;
+                }
+            }
+            if (cnt <= mid) {
+                l = mid + 1;
+            } else {
+                r = mid - 1;
+                ans = mid;
+            }
+        }
+        return ans;
+
+    }
+
+
+    /**
+     * 快慢指针:  类似于监测环
+     * 如果有重复，那么一定会成环，有环则一定会来回跳直至相遇
+     * 时间复杂度O(N)
+     * 速度击败92.87%  内存击败67.52%  4ms
+     * @param nums
+     * @return
+     */
+    public int findDuplicate2(int[] nums) {
+        int slow = 0, fast = 0;
+        do {
+            slow = nums[slow];//走一步
+            fast = nums[nums[fast]];//走两步
+        } while (slow != fast);
+        slow = 0;
+        while (slow != fast) {
+            slow = nums[slow];
+            fast = nums[fast];
+        }
+        return slow;
+    }
+
+
+}

Leecode/src/main/java/com/markilue/leecode/test/testMeiTuan.java

@@ -0,0 +1,71 @@
+package com.markilue.leecode.test;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+/**
+ *@BelongsProject: Leecode
+ *@BelongsPackage: com.markilue.leecode.test
+ *@Author: markilue
+ *@CreateTime: 2023-03-19  13:45
+ *@Description: TODO  尝试树形DP:构造一颗子树
+ *@Version: 1.0
+ */
+public class testMeiTuan {
+
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+
+        int num = sc.nextInt();
+        int[] energies = new int[num];
+
+        for (int i = 0; i < num; i++) {
+            energies[i] = sc.nextInt();
+        }
+
+        TreeNode[] nodeList = new TreeNode[num + 1];
+
+        for (int i = 0; i < num; i++) {
+            int i1 = sc.nextInt();
+            nodeList[i1] = new TreeNode(i1, energies[i]);
+        }
+
+        for (int i = 0; i < num - 1; i++) {
+            int v1 = sc.nextInt();
+            int v2 = sc.nextInt();
+            nodeList[v1].childList.add(nodeList[v2]);
+            nodeList[v2].childList.add(nodeList[v1]);
+        }
+
+        System.out.println(nodeList);
+
+    }
+}
+
+
+class TreeNode {
+
+
+    int value;
+    int energe;
+    List<TreeNode> childList = new ArrayList<>();//构造一个子树的子节点
+
+    public TreeNode() {
+    }
+
+    public TreeNode(int value) {
+        this.value = value;
+    }
+
+    public TreeNode(int value, int energe) {
+        this.value = value;
+        this.energe = energe;
+    }
+
+    public TreeNode(int value, List<TreeNode> childList) {
+        this.value = value;
+        this.childList = childList;
+    }
+
+}

interview/MeiTuan/src/main/java/com/markilue/interview/Question1.java

@@ -1,4 +1,5 @@
-package meituan;
+package com.markilue.interview;
+
 
 import org.junit.Test;
 

interview/MeiTuan/src/main/java/com/markilue/interview/Question2.java

@@ -1,4 +1,4 @@
-package meituan;
+package com.markilue.interview;
 
 import org.junit.Test;
 

interview/MeiTuan/src/main/java/com/markilue/interview/Question3.java

@@ -1,4 +1,4 @@
-package meituan;
+package com.markilue.interview;
 
 
 import org.junit.Test;

interview/MeiTuan/src/main/java/com/markilue/interview/Question4.java

@@ -1,4 +1,4 @@
-package meituan;
+package com.markilue.interview;
 
 import java.util.Arrays;
 import java.util.Scanner;

interview/MeiTuan/src/main/java/com/markilue/interview/Question5.java

@@ -1,4 +1,4 @@
-package meituan;
+package com.markilue.interview;
 
 
 import java.util.ArrayList;

interview/MiHayo/pom.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.markilue.interview</groupId>
+    <artifactId>MiHayo</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>8</maven.compiler.source>
+        <maven.compiler.target>8</maven.compiler.target>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>compile</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>RELEASE</version>
+            <scope>compile</scope>
+        </dependency>
+    </dependencies>
+
+</project>