Medium Google Interview Questions: Strategy Guide

Medium questions at Google typically represent the core of their technical interviews. These problems require more than just recalling a solution—they demand recognizing patterns, making trade-offs, and communicating your reasoning clearly. A Medium problem here often involves a twist on a known concept or combining two fundamental ideas, testing your adaptability and depth of understanding.

Common Patterns

Google’s Medium problems frequently test specific algorithmic patterns. Mastering these will help you decode many interview questions.

Two Pointers / Sliding Window: Used for array or string problems involving subarrays, subsequences, or paired comparisons.

def max_subarray_sum(nums, k):
    window_sum = sum(nums[:k])
    max_sum = window_sum
    for i in range(k, len(nums)):
        window_sum += nums[i] - nums[i - k]
        max_sum = max(max_sum, window_sum)
    return max_sum

Graph Traversal (BFS/DFS): Common for problems involving grids, relationships, or hierarchical data. Hash Maps for Frequency/Caching: Essential for optimization and reducing time complexity. Tree/Recursion: Often used for problems about binary trees, serialization, or recursive decision-making. Interval Merging/Overlap: Frequent in scheduling or range-based problems.

Time Targets

In a 45-minute interview, you should aim to solve a Medium problem within 25-30 minutes. This includes:

• 2-5 minutes: Clarifying the problem, asking edge cases, and restating your understanding.
• 10-15 minutes: Designing the approach, discussing trade-offs, and writing pseudocode.
• 10-15 minutes: Writing clean, correct code in your chosen language.
• Remaining time: Testing with examples, discussing optimizations, and analyzing complexity.

If you finish early, be prepared for a follow-up (e.g., a variation, optimization, or a second simpler question). Practice under timed conditions to build this pace.

Practice Strategy

Don’t just solve problems—practice deliberately.

1. Pattern-First Learning: Group problems by pattern (e.g., all “sliding window” questions). Solve until you recognize the pattern instantly.
2. Simulate the Interview: Use a timer. Verbalize your thinking as you solve. Write code on a whiteboard or in a plain text editor without autocomplete.
3. Review and Refactor: After solving, review the optimal solution. If your code was messy, rewrite it for clarity and efficiency.
4. Focus on Weaknesses: If you struggle with graphs, double your practice on BFS/DFS problems. Use Google’s tagged Medium questions to target specific areas.

Consistent, focused practice on these Medium problems builds the speed and pattern recognition needed to pass Google’s technical screens.

Practice Medium Google questions