feat: add ts solution to lc problem: No.530 (#2832)

Author: rain84

solution/0500-0599/0530.Minimum Absolute Difference in BST/README.md

@@ -253,6 +253,43 @@ impl Solution {
 }
 ```
 
+#### TypeScript
+
+```ts
+/**
+ * Definition for a binary tree node.
+ * class TreeNode {
+ *     val: number
+ *     left: TreeNode | null
+ *     right: TreeNode | null
+ *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
+ *         this.val = (val===undefined ? 0 : val)
+ *         this.left = (left===undefined ? null : left)
+ *         this.right = (right===undefined ? null : right)
+ *     }
+ * }
+ */
+function getMinimumDifference(root: TreeNode | null): number {
+    if (!root) return 0;
+
+    let prev = Number.MIN_SAFE_INTEGER;
+    let min = Number.MAX_SAFE_INTEGER;
+
+    const dfs = (node: TreeNode | null) => {
+        if (!node) return;
+
+        dfs(node.left);
+        min = Math.min(min, node.val - prev);
+        prev = node.val;
+        dfs(node.right);
+    };
+
+    dfs(root);
+
+    return min;
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/0500-0599/0530.Minimum Absolute Difference in BST/README_EN.md

@@ -246,6 +246,43 @@ impl Solution {
 }
 ```
 
+#### TypeScript
+
+```ts
+/**
+ * Definition for a binary tree node.
+ * class TreeNode {
+ *     val: number
+ *     left: TreeNode | null
+ *     right: TreeNode | null
+ *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
+ *         this.val = (val===undefined ? 0 : val)
+ *         this.left = (left===undefined ? null : left)
+ *         this.right = (right===undefined ? null : right)
+ *     }
+ * }
+ */
+function getMinimumDifference(root: TreeNode | null): number {
+    if (!root) return 0;
+
+    let prev = Number.MIN_SAFE_INTEGER;
+    let min = Number.MAX_SAFE_INTEGER;
+
+    const dfs = (node: TreeNode | null) => {
+        if (!node) return;
+
+        dfs(node.left);
+        min = Math.min(min, node.val - prev);
+        prev = node.val;
+        dfs(node.right);
+    };
+
+    dfs(root);
+
+    return min;
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/0500-0599/0530.Minimum Absolute Difference in BST/Solution.ts

@@ -0,0 +1,32 @@
+/**
+ * Definition for a binary tree node.
+ * class TreeNode {
+ *     val: number
+ *     left: TreeNode | null
+ *     right: TreeNode | null
+ *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
+ *         this.val = (val===undefined ? 0 : val)
+ *         this.left = (left===undefined ? null : left)
+ *         this.right = (right===undefined ? null : right)
+ *     }
+ * }
+ */
+function getMinimumDifference(root: TreeNode | null): number {
+    if (!root) return 0;
+
+    let prev = Number.MIN_SAFE_INTEGER;
+    let min = Number.MAX_SAFE_INTEGER;
+
+    const dfs = (node: TreeNode | null) => {
+        if (!node) return;
+
+        dfs(node.left);
+        min = Math.min(min, node.val - prev);
+        prev = node.val;
+        dfs(node.right);
+    };
+
+    dfs(root);
+
+    return min;
+}