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This is a hard difficulty Coding & Algorithms question, commonly asked during Onsite rounds at Deutschebank.

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This question is commonly asked for Software Engineer candidates at Deutschebank during technical interviews.

Solve tree equality and valid parentheses | Deutschebank Coding Question

Q: Solve tree equality and valid parentheses

This problem set evaluates core skills in data structures and algorithmic reasoning, specifically binary tree structural equality and bracket-matching for strings, testing understanding of tree traversal, recursion, and stack-based parsing.

Solve tree equality and valid parentheses

Company: Deutschebank

Role: Software Engineer

Category: Coding & Algorithms

Difficulty: hard

Interview Round: Onsite

You are asked to solve **two independent coding questions**. ## 1) Compare two binary trees for equality Given the roots of two binary trees `p` and `q`, return `true` if they are **structurally identical** and all corresponding nodes have the **same value**; otherwise return `false`. **Input:** Two tree roots `p`, `q` (each node has `val`, `left`, `right`). **Output:** Boolean. **Constraints (typical):** - `0 <= number_of_nodes <= 10^4` - Node values fit in 32-bit signed integer. ## 2) Validate bracket/parentheses string Given a string `s` consisting only of the characters `'(' , ')' , '{' , '}' , '[' , ']'`, determine whether the input string is **valid**. A string is valid if: 1. Open brackets are closed by the **same type** of brackets. 2. Open brackets are closed in the **correct order**. 3. Every close bracket has a corresponding earlier open bracket. **Input:** String `s`. **Output:** Boolean. **Constraints (typical):** - `0 <= |s| <= 10^5` ## Additional requirement After implementing each solution, write a few **test cases** that cover normal cases and edge cases.

Quick Answer: This problem set evaluates core skills in data structures and algorithmic reasoning, specifically binary tree structural equality and bracket-matching for strings, testing understanding of tree traversal, recursion, and stack-based parsing.

Compare Binary Trees For Equality

Trees are represented as [value,left,right] or None. Return whether two trees have identical structure and values.

Constraints

Inputs are Python literals matching the function signature.
Return a deterministic exact-match value.

Examples

Input: ([1,[2,None,None],[3,None,None]], [1,[2,None,None],[3,None,None]])

Expected Output: True

Explanation: Same structure and values.

Input: ([1,[2,None,None],None], [1,None,[2,None,None]])

Expected Output: False

Explanation: Different structure is not equal.

Input: (None, None)

Expected Output: True

Explanation: Two empty trees are equal.

Hints

Clarify edge cases before coding.
Keep the return value deterministic.

Validate Bracket String

Return whether a bracket string is valid with matching bracket types and order.

Constraints

Inputs are Python literals matching the function signature.
Return a deterministic exact-match value.

Examples

Input: ('()[]{}',)

Expected Output: True

Explanation: Every bracket closes correctly.

Input: ('([)]',)

Expected Output: False

Explanation: Incorrect nesting is invalid.

Input: ('',)

Expected Output: True

Explanation: The empty bracket string is valid.

Hints

Clarify edge cases before coding.
Keep the return value deterministic.

Quick Overview

This problem set evaluates core skills in data structures and algorithmic reasoning, specifically binary tree structural equality and bracket-matching for strings, testing understanding of tree traversal, recursion, and stack-based parsing.