count-good-nodes-in-binary-tree

.devcontainer/Dockerfile

@@ -4,6 +4,8 @@
 ARG VARIANT="buster"
 FROM mcr.microsoft.com/vscode/devcontainers/base:0-${VARIANT}
 
+RUN sudo apt install gnupg2 -y
+
 # ** [Optional] Uncomment this section to install additional packages. **
 # RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
 #     && apt-get -y install --no-install-recommends <your-package-list-here>

.devcontainer/devcontainer.json

@@ -14,7 +14,8 @@
 
 	// Add the IDs of extensions you want installed when the container is created.
 	"extensions": [
-		"rust-lang.rust-analyzer"
+		"rust-lang.rust-analyzer",
+		"LeetCode.vscode-leetcode"
 	],
 
 	// Use 'forwardPorts' to make a list of ports inside the container available locally.

.gitignore

@@ -1 +1,3 @@
-/target
+/target
+Cargo.lock
+Cargo.toml

.vscode/settings.json

@@ -0,0 +1,8 @@
+{
+    "leetcode.filePath": {
+        "default": {
+            "folder": "${kebab-case-name}",
+            "filename": "sol.${ext}"
+        }
+    }
+}

3-sum-closest/sol.rs

@@ -0,0 +1,33 @@
+
+/*
+ * @lc app=leetcode id=16 lang=rust
+ *
+ * [16] 3Sum Closest
+ */
+struct Solution {}
+
+// @lc code=start
+use std::cmp::Ordering;
+
+impl Solution {
+    pub fn three_sum_closest(mut nums: Vec<i32>, target: i32) -> i32 {
+        nums.sort_unstable();
+        let mut result = nums[0] + nums[1] + nums[2];
+        for (i, &n) in nums.iter().enumerate() {
+            let (mut l, mut r) = (i + 1, nums.len() - 1);
+            while l < r {
+                let sum = n + nums[l] + nums[r];
+                if (target - sum).abs() < (target - result).abs() {
+                    result = sum;
+                }
+                match sum.cmp(&target) {
+                    Ordering::Equal => return sum,
+                    Ordering::Less => l += 1,
+                    Ordering::Greater => r -= 1
+                }
+            }
+        }
+        result
+    }
+}
+// @lc code=end

count-good-nodes-in-binary-tree/sol.go

@@ -0,0 +1,44 @@
+/*
+ * @lc app=leetcode id=1448 lang=golang
+ *
+ * [1448] Count Good Nodes in Binary Tree
+ */
+package main
+
+// @lc code=start
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+import "math"
+
+func goodNodes(root *TreeNode) int {
+	return subGoodNodes(root, math.MinInt)
+}
+
+func subGoodNodes(root *TreeNode, previousMax int) int {
+	if root == nil {
+		return 0
+	}
+	sum := 0
+	max := previousMax
+	if root.Val >= previousMax {
+		sum = 1
+		max = root.Val
+	}
+	sum += subGoodNodes(root.Left, max)
+	sum += subGoodNodes(root.Right, max)
+	return sum
+}
+
+// @lc code=end
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}