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This is a medium difficulty Coding & Algorithms question, commonly asked during Technical Screen rounds at Microsoft.

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

Solve Three Coding Interview Problems | Microsoft Coding Question

Quick Overview

This set of problems evaluates competency in algorithmic problem-solving, including merging sorted arrays with duplicate elimination, reasoning about the extremum of a quadratic function within integer bounds, and the design and implementation of prefix-based string search, and falls within the Coding & Algorithms category.

Solve Three Coding Interview Problems

Company: Microsoft

Role: Software Engineer

Category: Coding & Algorithms

Difficulty: medium

Interview Round: Technical Screen

The coding round contained three independent problems: 1. **Merge two sorted arrays and remove duplicates.** Given two sorted integer arrays `a` and `b`, return one sorted array that contains each distinct value appearing in either array exactly once. 2. **Find the vertex of a quadratic function within a range.** You can evaluate a quadratic function `f(x)` on integer inputs, and you are given an integer range `[L, R]` that is guaranteed to contain the vertex of the parabola. Find the integer `x` where the function reaches its extremum within that range. 3. **Design and implement a simplified search autocomplete system.** Build a data structure initialized with a collection of strings. It should support inserting a new string and querying a prefix to return all stored strings that begin with that prefix. Unlike a production autocomplete system, you do not need frequency-based ranking or top-`k` truncation.

Quick Answer: This set of problems evaluates competency in algorithmic problem-solving, including merging sorted arrays with duplicate elimination, reasoning about the extremum of a quadratic function within integer bounds, and the design and implementation of prefix-based string search, and falls within the Coding & Algorithms category.

Merge Two Sorted Arrays Without Duplicates

Return one sorted array containing every distinct value from two sorted input arrays.

Constraints

Inputs are provided as Python literals matching the function signature.
Return a deterministic exact-match result.

Examples

Input: ([1,2,2,4], [2,3,4,5])

Expected Output: [1, 2, 3, 4, 5]

Explanation: Duplicates across arrays.

Input: ([], [1,1,2])

Expected Output: [1, 2]

Explanation: One array empty.

Input: ([-3,-1], [-2,-1])

Expected Output: [-3, -2, -1]

Explanation: Negative values.

Hints

Choose a representation that makes the core operation simple.
Handle empty and boundary inputs before the main algorithm.

Quadratic Extremum in an Integer Range

Given coefficients a, b, c and an integer range, return the integer x where ax^2+bx+c reaches its extremum in the range plus the value.

Constraints

Inputs are provided as Python literals matching the function signature.
Return a deterministic exact-match result.

Examples

Input: (1, -4, 1, 0, 5)

Expected Output: {'x': 2, 'value': -3}

Explanation: Minimum near vertex x=2.

Input: (-1, 6, 0, 0, 10)

Expected Output: {'x': 3, 'value': 9}

Explanation: Maximum near vertex x=3.

Input: (2, 0, 0, 5, 7)

Expected Output: {'x': 5, 'value': 50}

Explanation: Vertex outside range, use boundary.

Hints

Choose a representation that makes the core operation simple.
Handle empty and boundary inputs before the main algorithm.

Simplified Search Autocomplete

Maintain a set of strings and return sorted matches for prefix queries after optional insertions.

Constraints

Inputs are provided as Python literals matching the function signature.
Return a deterministic exact-match result.

Examples

Input: (['app','apple','bat'], [['query','app'], ['insert','application'], ['query','app'], ['query','b']])

Expected Output: [['app', 'apple'], None, ['app', 'apple', 'application'], ['bat']]

Explanation: Insert affects later queries.

Input: ([], [['query','a'], ['insert','a'], ['query','a']])

Expected Output: [[], None, ['a']]

Explanation: Empty initial set.

Hints

Choose a representation that makes the core operation simple.
Handle empty and boundary inputs before the main algorithm.

Quick Overview