feat(redo): 添加 LeetCode75、124 和300 的解决方案

- LeetCode75: 实现了颜色分类问题的解决方案
- LeetCode124: 提供了二叉树中的最大路径和问题的解答
- LeetCode300: 完成了最长递增子序列问题的实现

ForJdk17/src/main/java/cn/whaifree/redo/redo_all_241121/LeetCode124.java

@@ -0,0 +1,50 @@
+package cn.whaifree.redo.redo_all_241121;
+
+import cn.whaifree.leetCode.model.TreeNode;
+import org.junit.Test;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/23 12:32
+ * @注释
+ */
+public class LeetCode124 {
+
+    @Test
+    public void test() {
+        TreeNode treeNode = TreeNode.constructTree(new Integer[]{9, 9, 20, null, null, 15, 7});
+        System.out.println(new Solution().maxPathSum(treeNode));
+    }
+
+    class Solution {
+        int max = Integer.MIN_VALUE;
+        /**
+         * 每个节点的路径来源于 左边 右边 上面
+         * @param root
+         * @return
+         */
+        public int maxPathSum(TreeNode root) {
+            int in = in(root);
+            return max;
+        }
+
+        public int in(TreeNode root) {
+            if (root == null) {
+                return 0;
+            }
+
+            int left = in(root.left);
+            if (left < 0) {
+                left = 0;// 左边拖后腿，直接不采用
+            }
+            int right = in(root.right);
+            if (right < 0) {
+                right = 0;// 右边拖后腿，直接不采用
+            }
+            max = Math.max(max, left + right + root.val);
+            return Math.max(left, right) + root.val;
+        }
+
+    }
+}

ForJdk17/src/main/java/cn/whaifree/redo/redo_all_241121/LeetCode300.java

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+package cn.whaifree.redo.redo_all_241121;
+
+import org.junit.Test;
+
+import java.util.Arrays;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/21 22:50
+ * @注释
+ */
+public class LeetCode300 {
+    @Test
+    public void test() {
+        Solution solution = new Solution();
+        int[] nums = {10,9,2,5,3,7,101,18};
+        System.out.println(solution.lengthOfLIS(nums));
+    }
+
+
+    class Solution {
+        /**
+         * 最长递增子序列
+         * [10,9,2,5,3,7,101,18]
+         *  1  1 1 2
+         *
+         *  right从左到右
+         *  left 往左搜索到0，找到有序列更大的
+         * @param nums
+         * @return
+         */
+        public int lengthOfLIS(int[] nums) {
+            int[] dp = new int[nums.length];
+            Arrays.fill(dp, 1);
+            int max = 1;
+            for (int right = 1; right < nums.length; right++) {
+                int left = right - 1;
+                while (left >= 0) {
+                    if (nums[left] < nums[right]) {
+                        dp[right] = Math.max(dp[left] + 1, dp[right]);
+                    }
+                    left--;
+                }
+            }
+            return max;
+        }
+    }
+}

ForJdk17/src/main/java/cn/whaifree/redo/redo_all_241121/LeetCode75.java

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+package cn.whaifree.redo.redo_all_241121;
+
+/**
+ * @version 1.0
+ * @Author whai文海
+ * @Date 2024/11/21 22:44
+ * @注释
+ */
+public class LeetCode75 {
+
+    class Solution {
+        public void sortColors(int[] nums) {
+            int left = 0;
+            int right = 0;
+            for (int i = 0; i < nums.length; i++) {
+                if (nums[i] == 0) {
+                    swap(nums, i, left);
+                    if (nums[i] == 1) { // 有可能index0是1，然后没有这一段就会被换到最后去哦
+                        swap(nums, i, right);
+                    }
+                    left++;
+                    right++;
+                }else if (nums[i] == 1) {
+                    swap(nums, i, right);
+                    right++;
+                }
+            }
+        }
+        public void swap(int[] nums, int i, int j) {
+            int temp = nums[i];
+            nums[i] = nums[j];
+            nums[j] = temp;
+        }
+    }
+}