added leafSimilar

Author: shkvik

src/bst/leaf-similar.ts

@@ -0,0 +1,57 @@
+import { createBinaryTree, TreeNode } from "./utilities";
+
+/**
+ * @problem
+ * [872. Leaf-Similar Trees](https://leetcode.com/problems/leaf-similar-trees)
+ */
+function leafSimilar(root1: TreeNode, root2: TreeNode): boolean {
+  const getLeafs = (root: TreeNode): number[] => {
+    if (!root.left && !root.right) {
+      return [root.val];
+    }
+    const left = root.left ? getLeafs(root.left) : [];
+    const right = root.right ? getLeafs(root.right) : [];
+    return [...left, ...right];
+  }
+  const root1Leafs = getLeafs(root1).join('#');
+  const root2Leafs = getLeafs(root2).join('#');
+  return root1Leafs === root2Leafs;
+};
+
+export function leafSimilarDBG() {
+  const tests = [
+    {
+      input: {
+        root1: createBinaryTree([3, 5, 1, 6, 2, 9, 8, null, null, 7, 4]),
+        root2: createBinaryTree([3, 5, 1, 6, 7, 4, 2, null, null, null, null, null, null, 9, 8])
+      },
+      result: true
+    },
+    {
+      input: {
+        root1: createBinaryTree([1, 2, 3]),
+        root2: createBinaryTree([1, 3, 2])
+      },
+      result: false
+    },
+    {
+      input: {
+        root1: createBinaryTree([1]),
+        root2: createBinaryTree([1])
+      },
+      result: true
+    },
+  ];
+
+  tests.forEach((test, index) => {
+    const output = leafSimilar(test.input.root1, test.input.root2);
+    const success = output === test.result;
+    if (success) {
+      console.log(`${index} success`);
+    } else {
+      console.log(`${index} fail`);
+      console.log(`expected ${test.result}`);
+      console.log(`got ${output}`);
+    }
+  });
+}

src/bst/utilities/bst.utilities.ts

@@ -37,4 +37,33 @@ export function printTree(node: TreeNode): void {
       _printTree(node.left, childPrefix, false, false);
     }
   }
+}
+
+export function createBinaryTree(values: (number | null)[]): TreeNode | null {
+  if (values.length === 0 || values[0] == null) return null;
+
+  const root = new TreeNode(values[0]);
+  const queue: (TreeNode | null)[] = [root];
+  let i = 1;
+
+  while (i < values.length) {
+    const current = queue.shift();
+    if (!current) continue;
+
+    const leftVal = values[i++];
+    if (leftVal != null) {
+      current.left = new TreeNode(leftVal);
+      queue.push(current.left);
+    }
+
+    if (i >= values.length) break;
+
+    const rightVal = values[i++];
+    if (rightVal != null) {
+      current.right = new TreeNode(rightVal);
+      queue.push(current.right);
+    }
+  }
+
+  return root;
 }

src/main.ts

@@ -1,4 +1,3 @@
-import { deleteMiddleDBG } from "./linked_list/delete-middle";
-import { oddEvenListDBG } from "./linked_list/odd-even-list";
+import { leafSimilarDBG } from "./bst/leaf-similar";
 
-oddEvenListDBG()
+leafSimilarDBG()