add Subtree of Another Tree solution

Author: HoonDongKang

subtree-of-another-tree/HoonDongKang.ts

@@ -0,0 +1,26 @@
+/**
+ * [Problem]: [572] Subtree of Another Tree
+ * (https://leetcode.com/problems/subtree-of-another-tree/description/)
+ */
+
+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;
+    }
+}
+
+//시간복잡도 O(n*m)
+//공간복잡도 O(n+m)
+function isSubtree(root: TreeNode | null, subRoot: TreeNode | null): boolean {
+    const pre = (node: TreeNode | null) => {
+        if (!node) return "N";
+        return `(${node.val},${pre(node.left)},${pre(node.right)})`;
+    };
+
+    return pre(root).includes(pre(subRoot));
+}