Google vs Cisco: Interview Question Comparison

When preparing for technical interviews, understanding company-specific patterns is crucial. Google and Cisco, while both requiring strong algorithmic skills, present distinct landscapes in question volume, difficulty, and focus areas. Google's process is famously rigorous and broad, while Cisco's tends to be more focused on practical, implementation-oriented problems. Your preparation strategy should differ accordingly.

Question Volume and Difficulty

The data reveals a stark difference in scale. Google has a tagged question bank of over 2,200 problems (2217: 588 Easy, 1153 Medium, 476 Hard), while Cisco's is under 100 (86: 22 Easy, 49 Medium, 15 Hard).

This disparity reflects the nature of their hiring processes. Google's immense volume stems from its standardized, highly competitive process for software engineering roles, which is designed to assess fundamental problem-solving and algorithmic mastery across a vast array of concepts. The high proportion of Medium and Hard questions indicates an expectation to handle complex optimizations and novel scenarios.

Cisco's smaller, more manageable question bank suggests a more targeted interview. The questions often relate more directly to networking, systems, and practical software engineering challenges the company faces. The difficulty distribution (with Medium being the most common) points to an emphasis on solid implementation and reasoning over solving esoteric algorithmic puzzles.

Topic Overlap

Both companies heavily test Array, String, and Hash Table operations. These are foundational data structures for efficient data manipulation and are ubiquitous in software development.

The key differentiator is in the advanced topics. Dynamic Programming (DP) is a major focus for Google, as seen by its prominence in their topic list. DP questions are classic for testing optimal substructure and state management thinking. Cisco's list highlights Two Pointers, a technique crucial for optimizing array/string problems (e.g., sliding window, searching in sorted data) and is highly practical for system-level programming.

Google's Focus: Array/String + Hash Table + Dynamic Programming + Graph + Tree. Cisco's Focus: Array/String + Hash Table + Two Pointers + likely more systems design/basic OOP.

For example, a typical Google question might involve DP:

# Leetcode 322. Coin Change (Classic DP)
def coinChange(coins, amount):
    dp = [float('inf')] * (amount + 1)
    dp[0] = 0
    for i in range(1, amount + 1):
        for coin in coins:
            if i - coin >= 0:
                dp[i] = min(dp[i], dp[i - coin] + 1)
    return dp[amount] if dp[amount] != float('inf') else -1

A common Cisco-style problem might use two pointers:

# Leetcode 15. 3Sum (Uses sorting + two pointers)
def threeSum(nums):
    nums.sort()
    res = []
    for i in range(len(nums)):
        if i > 0 and nums[i] == nums[i-1]:
            continue
        l, r = i + 1, len(nums) - 1
        while l < r:
            total = nums[i] + nums[l] + nums[r]
            if total < 0:
                l += 1
            elif total > 0:
                r -= 1
            else:
                res.append([nums[i], nums[l], nums[r]])
                l += 1
                while l < r and nums[l] == nums[l-1]:
                    l += 1
    return res

Which to Prepare for First

Prepare for Cisco first. Its focused question bank allows you to build core competency in fundamental data structures and essential techniques like two pointers efficiently. Mastering Cisco's ~86 questions provides a strong, practical foundation. You can achieve readiness in a shorter timeframe.

Then, transition to Google. Use the vast Google question bank as an extensive training ground to deepen your algorithmic knowledge. Treat it as advanced study where you encounter complex DP, graph, and system design problems. Preparing for Google will inherently cover the fundamentals needed for Cisco, but the reverse is not true.

In short: solidify your basics with Cisco's targeted list, then scale up to Google's comprehensive challenge.

For more detailed question breakdowns, visit the company pages: Google Interview Questions | Cisco Interview Questions