Dunzo Placement Papers 2025

Overview

This page is a working set of Dunzo placement papers from 2025: from student reports questions, the 2025 online assessment pattern, and step-by-step solutions. Use it to see what Dunzo actually asked in the latest cycle, how hard the rounds were, and which themes (DSA, system design, aptitude, or role-specific topics) mattered most. Practice the problems below under timed conditions, then cross-check with the interview and preparation guides if you are targeting an upcoming Dunzo drive.

2025 Updates

The 2025 Dunzo placement process maintains focus on DSA and system design with enhanced emphasis on logistics optimization.

Dunzo Online Assessment 2025 pattern

Section	Questions	Time	Difficulty
Coding Problems	2-3	90 min	Medium-Hard

Dunzo Placement Papers 2025 - actual questions & solutions

This section contains practice questions styled on Dunzo placement papers 2025 (recent-cycle pattern), with worked solutions. Use them as timed sectional drills - from student reports drives vary by college and role, so treat this as a high-signal practice bank, not an official paper dump.

Question 1: reverse a string

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Problem Statement: Given a string, return it reversed.

Example:

Input: "placement"
Output: "tnemecalp"

Solution (Java):

public String reverse(String s) {
    return new StringBuilder(s).reverse().toString();
}

Time Complexity: O(n)
Space Complexity: O(n)

Question 2: first non-repeating character

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Problem Statement: Return the first non-repeating character in a string, or ‘_’ if none.

Example:

Input: "swiss"
Output: 'w'

Solution (Java):

public char firstUnique(String s) {
    int[] freq = new int[256];
    for (char c : s.toCharArray()) freq[c]++;
    for (char c : s.toCharArray()) if (freq[c] == 1) return c;
    return '_';
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 3: merge two sorted lists

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Problem Statement: Merge two sorted linked lists and return a new sorted list.

Example:

Input: 1→2→4 , 1→3→4
Output: 1→1→2→3→4→4

Solution (Java):

public ListNode mergeTwoLists(ListNode a, ListNode b) {
    ListNode dummy = new ListNode(0), cur = dummy;
    while (a != null && b != null) {
        if (a.val <= b.val) { cur.next = a; a = a.next; }
        else { cur.next = b; b = b.next; }
        cur = cur.next;
    }
    cur.next = (a != null) ? a : b;
    return dummy.next;
}

Time Complexity: O(n + m)
Space Complexity: O(1)

Question 4: maximum subarray sum

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Problem Statement: Find the contiguous subarray with the largest sum.

Example:

Input: [-2, 1, -3, 4, -1, 2, 1, -5, 4]
Output: 6  // [4, -1, 2, 1]

Solution (Java):

public int maxSubArray(int[] nums) {
    int best = nums[0], cur = nums[0];
    for (int i = 1; i < nums.length; i++) {
        cur = Math.max(nums[i], cur + nums[i]);
        best = Math.max(best, cur);
    }
    return best;
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 5: climbing stairs

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Problem Statement: You can climb 1 or 2 steps. How many distinct ways to climb n stairs?

Example:

Input: n = 4
Output: 5

Solution (Java):

public int climbStairs(int n) {
    if (n <= 2) return n;
    int a = 1, b = 2;
    for (int i = 3; i <= n; i++) {
        int c = a + b; a = b; b = c;
    }
    return b;
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 6: detect cycle in linked list

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Problem Statement: Return true if the linked list has a cycle.

Example:

Input: 3→2→0→-4→(back to 2)
Output: true

Solution (Java):

public boolean hasCycle(ListNode head) {
    ListNode slow = head, fast = head;
    while (fast != null && fast.next != null) {
        slow = slow.next;
        fast = fast.next.next;
        if (slow == fast) return true;
    }
    return false;
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 7: rotate array right by k

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Problem Statement: Rotate the array to the right by k steps.

Example:

Input: [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]

Solution (Java):

public void rotate(int[] nums, int k) {
    k %= nums.length;
    reverse(nums, 0, nums.length - 1);
    reverse(nums, 0, k - 1);
    reverse(nums, k, nums.length - 1);
}
void reverse(int[] a, int l, int r) {
    while (l < r) { int t = a[l]; a[l++] = a[r]; a[r--] = t; }
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 8

Q8: Virtual memory is typically implemented using?

Solution:

OS uses demand paging (and sometimes segmentation) to implement virtual memory.

Answer: Demand paging

Question 9

Q9: In OOP, hiding internal details and showing only essential features is called?

Solution:

This is the definition of Encapsulation (often paired with abstraction in interviews).

Answer: Encapsulation

Question 10

Q10: Which normal form removes transitive dependency?

Solution:

1NF: atomic values. 2NF: no partial dependency. 3NF: no transitive dependency.

Answer: 3NF

Question 11

Q11: Which protocol is connection-oriented at the transport layer?

Solution:

TCP is connection-oriented; UDP is connectionless.

Answer: TCP

Key insights from 2025 Dunzo Online Assessment

1. Coding Section is Critical: Must solve 2-3 coding problems correctly to advance
2. Logistics Optimization Focus: Strong emphasis on logistics systems, route optimization, real-time delivery tracking
3. Time Management: 2-3 problems in 90 minutes requires excellent speed and accuracy
4. Success Rate: Only 10-15% cleared OA and advanced to interviews
5. Platform: Dunzo assessment platform or HackerRank
6. Focus Areas: Arrays, trees, graphs, dynamic programming, logistics systems, real-time tracking
7. Enhanced Emphasis: Optimal solutions, logistics optimization, and real-time delivery tracking systems

Dunzo 2025 interview experiences

Based on recent candidate experiences from 2025 Dunzo interviews:

2025 Interview Process:

1. Online Assessment (90 minutes): 2-3 coding problems
2. Technical Phone Screen (45-60 minutes): Coding problems, algorithm discussions, logistics concepts, real-time tracking
3. Onsite/Virtual Interviews (4-5 rounds, 45-60 minutes each):

• Coding rounds (2-3): Algorithms, data structures, problem-solving
• System Design rounds: Logistics optimization platforms, route optimization, real-time delivery tracking, delivery management
• Behavioral rounds: Problem-solving approach, logistics passion, impact

2025 Interview Trends:

• Increased emphasis on logistics optimization and real-time delivery tracking
• More focus on optimal solutions and modern logistics technologies
• Enhanced behavioral questions about innovation and logistics passion
• Questions about logistics optimization and real-time tracking systems

Common 2025 Interview Topics:

• Coding: Arrays, strings, trees, graphs, dynamic programming, route optimization algorithms, real-time tracking
• System Design: Logistics optimization platforms, route optimization, real-time delivery tracking, delivery management
• Behavioral: Problem-solving, logistics passion, teamwork, impact
• Dunzo Technologies: Logistics optimization platforms, route optimization, real-time delivery tracking, delivery management

Success Tips:

• Strong coding performance is essential - solve problems optimally
• Understand logistics concepts, route optimization, and real-time tracking systems
• Practice system design for logistics optimization platforms and real-time tracking
• Prepare examples demonstrating problem-solving and logistics passion
• Learn Dunzo’s products and logistics technologies
• Practice explaining your thought process clearly

For detailed interview experiences from 2025, visit Dunzo Interview Experience page.

Preparation tips for Dunzo 2025 pattern

1. Master Coding Fundamentals: Focus on solving 2-3 coding problems correctly - arrays, trees, graphs, DP
2. Logistics Expertise: Strong understanding of logistics optimization systems, route optimization, real-time delivery tracking
3. Practice Previous Year Papers: Solve Dunzo OA papers from 2020-2025 to understand evolving patterns
4. Time Management: Practice completing 2-3 coding problems in 90 minutes
5. LeetCode Practice: Solve 200+ LeetCode problems focusing on arrays, strings, trees, graphs (medium-hard difficulty)
6. Logistics Focus: Practice problems related to logistics systems and route optimization
7. System Design Mastery: Learn logistics optimization platform design, route optimization, real-time delivery tracking
8. Dunzo Technologies: Learn logistics optimization platforms, route optimization, real-time delivery tracking, delivery management
9. Behavioral Preparation: Prepare examples using STAR format - problem-solving, logistics passion, impact
10. Mock Tests: Take timed practice tests to improve speed and accuracy

Comments & Suggestions

Related resources

2024 papers→

Coding questions→

Interview experience→

Preparation guide→

Dunzo hub→

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