Cisco vs ServiceNow: Interview Question Comparison

When preparing for technical interviews at major tech companies, understanding the specific patterns and expectations of each employer is crucial. Cisco and ServiceNow, while both established technology firms, present distinct interview landscapes in terms of question volume, difficulty distribution, and core topic focus. A strategic candidate will tailor their preparation to these differences rather than using a generic approach.

Question Volume and Difficulty

The data shows a clear difference in the scale and challenge level of their question banks.

Cisco has a larger overall pool with 86 questions, categorized as Easy (22), Medium (49), and Hard (15). This indicates a broad range of problems, with a significant majority (74%) falling into the Medium and Hard categories. The presence of 15 Hard questions suggests you must be prepared for complex algorithmic challenges that test deep understanding and optimization.

ServiceNow, with 78 questions, has a dramatically different difficulty spread: only 8 Easy, 58 Medium, and 12 Hard. This profile is notably more intense, with a staggering 90% of questions at Medium or Hard difficulty. The Medium-heavy focus (58 questions) means you can expect a consistent barrage of problems that require more than just a naive solution; you'll need to demonstrate efficient, well-structured approaches under pressure.

In short, Cisco's test is broad with a notable hard tier, while ServiceNow's is a concentrated, sustained test of medium-to-high competency.

Topic Overlap

Both companies heavily test foundational data structures, but with a key divergence.

Shared Core Topics: Array, String, and Hash Table problems are central to both. You must be fluent in manipulating these structures. Two-pointer techniques, sliding windows, and hash map indexing for lookups or frequency counting are essential skills for these shared areas.

Key Differentiators:

• Cisco explicitly lists Two Pointers as a top topic. This signals a high probability of problems involving sorted array manipulation, palindrome checks, or linked list cycles.
• ServiceNow explicitly lists Dynamic Programming as a top topic. This is a major distinction. You must be prepared for classic DP problems (knapsack, coin change, longest common subsequence) and, more importantly, for recognizing when a problem has an optimal substructure that can be solved with memoization or tabulation.

Here is a quick example of a Two Pointers problem (common at Cisco) versus a DP problem (common at ServiceNow):

# Cisco-style: Two Pointers (Remove Duplicates from Sorted Array)
def removeDuplicates(nums):
    if not nums:
        return 0
    write = 1
    for read in range(1, len(nums)):
        if nums[read] != nums[read - 1]:
            nums[write] = nums[read]
            write += 1
    return write

# ServiceNow-style: Dynamic Programming (Climbing Stairs)
def climbStairs(n):
    if n <= 2:
        return n
    dp = [0] * (n + 1)
    dp[1], dp[2] = 1, 2
    for i in range(3, n + 1):
        dp[i] = dp[i - 1] + dp[i - 2]
    return dp[n]

Which to Prepare for First

Your preparation priority should be dictated by your timeline and the depth of your foundational knowledge.

If you are earlier in your interview prep journey or strengthening fundamentals, start with Cisco. Its larger number of Easy questions and slightly lower concentration of Hard problems provides a more graduated learning curve. Mastering the core Array, String, Hash Table, and Two Pointers patterns for Cisco will build a robust foundation that is 100% applicable to ServiceNow's shared topics.

If you are already comfortable with core data structures and algorithms and need to ramp up for intense problem-solving, or if your interview with ServiceNow is sooner, prioritize ServiceNow. Its 90% Medium/Hard distribution demands high proficiency. Focusing here will force you to optimize your solutions and tackle the significant additional challenge of Dynamic Programming. Successfully preparing for ServiceNow's bar will make Cisco's question bank feel more manageable, though you must circle back to specifically practice Cisco's highlighted Two Pointers problems.

Ultimately, the shared core means preparation for one benefits the other. The strategic difference lies in the additional, company-specific emphasis: master Two Pointers for Cisco, and master Dynamic Programming for ServiceNow.

For targeted practice, visit the Cisco and ServiceNow question banks: Cisco Interview Questions | ServiceNow Interview Questions