2026-03-31 00:29

Author: SilverRainZ

src/p/leetcode/index.rst

@@ -907,7 +907,6 @@ Merge Sorted Array
    :id: merge-sorted-array
    :diffculty: Easy
    :language: go
-   :key: 排序
    :date: 2026-03-05
 
 很简单的一道题，要不先把 nums1 挪开然后直接合并，要不逆序。之前想复杂了。
@@ -997,3 +996,55 @@ Jump Game II
 
 解法 2
    其实和 1 一样，但利用 `farest` 和 `end` 两个变量配合消除了内部循环，保证 `O(n)`
+
+Minimum Absolute Difference In Bst
+----------------------------------
+
+.. leetcode:: _
+   :id: minimum-absolute-difference-in-bst
+   :diffculty: Easy
+   :language: Go
+   :key: 二叉搜索树
+   :date: 2026-03-30
+
+转化为：有序序列里相邻的哪两个数间隔最小。然后中序遍历。
+
+Kth Smallest Element In A Bst
+-----------------------------
+
+.. leetcode:: _
+   :id: kth-smallest-element-in-a-bst
+   :diffculty: Medium
+   :language:
+   :key: 二叉搜索树
+   :date: 2026-03-30
+
+Validate Binary Search Tree
+---------------------------
+
+.. leetcode:: _
+   :id: validate-binary-search-tree
+   :diffculty: Medium
+   :language: go
+   :key: 二叉搜索树
+   :date: 2026-03-30
+
+Search Insert Position
+----------------------
+
+.. leetcode:: _
+   :id: search-insert-position
+   :diffculty: Easy
+   :language: go
+   :key: 二分查找
+   :date: 2026-03-30
+
+Search A 2D Matrix
+------------------
+
+.. leetcode:: _
+   :id: search-a-2d-matrix
+   :diffculty: Medium
+   :language: go
+   :key: 二分查找
+   :date: 2026-03-30

src/p/leetcode/kth-smallest-element-in-a-bst/go.mod

@@ -0,0 +1,3 @@
+module kth-smallest-element-in-a-bst
+
+go 1.26.1

src/p/leetcode/kth-smallest-element-in-a-bst/main.go

@@ -0,0 +1,32 @@
+package main
+
+import "fmt"
+
+type TreeNode struct {
+	Val int
+	Left *TreeNode
+	Right *TreeNode
+}
+
+func kthSmallest(root *TreeNode, k int) int {
+	cnt := 1
+	return visit(root, k, &cnt)
+}
+
+func visit(n *TreeNode, k int, cnt *int) int {
+	if n == nil {
+		return -1
+	}
+	if kth := visit(n.Left, k, cnt); kth != -1 {
+		return kth
+	}
+	if *cnt == k {
+		return n.Val
+	}
+	*cnt = *cnt + 1
+	return visit(n.Right, k, cnt)
+}
+
+func main() {
+	fmt.Println("vim-go")
+}

src/p/leetcode/minimum-absolute-difference-in-bst/go.mod

@@ -0,0 +1,3 @@
+module minimum-absolute-difference-in-bst
+
+go 1.26.1

src/p/leetcode/minimum-absolute-difference-in-bst/main.go

@@ -0,0 +1,37 @@
+package main
+
+import "fmt"
+import "math"
+
+type TreeNode struct {
+    Val int
+    Left *TreeNode
+    Right *TreeNode
+}
+
+func getMinimumDifference(root *TreeNode) int {
+	prev := -1
+	min := math.MaxInt
+	visit(root, &prev, &min)
+	return min
+}
+
+func visit(n *TreeNode, prev *int, min *int) {
+	if n == nil {
+		return 
+	}
+	visit(n.Left, prev, min)
+	// fmt.Println("visit:", n.Val, "prev:", *prev)
+	if *prev != -1 {
+		v := n.Val - *prev
+		if *min > v {
+			*min = v
+		}
+	}
+	*prev = n.Val
+	visit(n.Right, prev, min)
+}
+
+func main() {
+	fmt.Println("Hello, World!")
+}

src/p/leetcode/search-a-2d-matrix/go.mod

@@ -0,0 +1,3 @@
+module search-a-2d-matrix
+
+go 1.26.1

src/p/leetcode/search-a-2d-matrix/main.go

@@ -0,0 +1,32 @@
+package main
+
+import "fmt"
+
+func searchMatrix(matrix [][]int, target int) bool {
+	return binarySearch(matrix, target, 0, len(matrix) * len(matrix[0]))
+}
+
+func access(matrix [][]int, i int) int {
+	N := len(matrix[0])
+	m, n := i/N, i%N
+	return matrix[m][n]
+}
+
+func binarySearch(matrix [][]int, target int, left, right int) bool {
+	if left == right {
+		return false
+	}
+	mid := (left + right) / 2
+	v := access(matrix, mid) 
+	if v == target {
+		return true
+	} else if v > target {
+		return binarySearch(matrix, target, left, mid)
+	} else {
+		return binarySearch(matrix, target, mid+1, right)
+	}
+}
+
+func main() {
+	fmt.Println(searchMatrix([][]int{{1}}, 2))
+}

src/p/leetcode/search-insert-position/go.mod

@@ -0,0 +1,3 @@
+module search-insert-position
+
+go 1.26.1

src/p/leetcode/search-insert-position/main.go

@@ -0,0 +1,29 @@
+package main
+
+import "fmt"
+
+func searchInsert(nums []int, target int) int {
+	return binarySearch(nums, target, 0, len(nums))
+}
+
+func binarySearch(nums []int, target int, left, right int) int {
+	// fmt.Println("l r", left, right)
+	if left == right {
+		return left
+	}
+	mid := (left + right)/2
+	if nums[mid] == target {
+		return mid
+	} else if nums[mid] < target {
+		return binarySearch(nums, target, mid+1, right)
+	} else {
+		return binarySearch(nums, target, left, mid)
+	}
+}
+
+func main() {
+	fmt.Println(searchInsert([]int{1,3,5,6}, 5))
+	fmt.Println(searchInsert([]int{1,3,5,6}, 2))
+	fmt.Println(searchInsert([]int{1,3,5,6}, 7))
+	fmt.Println(searchInsert([]int{1,2,5,6}, 2))
+}

src/p/leetcode/validate-binary-search-tree/go.mod

@@ -0,0 +1,3 @@
+module validate-binary-search-tree
+
+go 1.26.1