Paypal Placement Papers 2025

Overview

This page is a working set of PayPal placement papers from 2025: from student reports questions, the 2025 online assessment pattern, and step-by-step solutions. Use it to see what PayPal 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 PayPal drive.

Paypal Online Assessment 2025 pattern

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

Paypal Placement Papers 2025 - actual questions & solutions

This section contains practice questions styled on PayPal 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: first non-repeating character

Show solution

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 2: valid parentheses

Show solution

Problem Statement: Given a string of brackets, determine if it is valid.

Example:

Input: "()[]{}"
Output: true

Solution (Java):

public boolean isValid(String s) {
    Deque<Character> st = new ArrayDeque<>();
    Map<Character, Character> pair = Map.of(')', '(', ']', '[', '}', '{');
    for (char c : s.toCharArray()) {
        if (pair.containsValue(c)) st.push(c);
        else if (st.isEmpty() || st.pop() != pair.get(c)) return false;
    }
    return st.isEmpty();
}

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

Question 3: reverse a string

Show solution

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 4: detect cycle in linked list

Show solution

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 5: binary tree level order

Show solution

Problem Statement: Return the level-order traversal of a binary tree.

Example:

Input: [3,9,20,null,null,15,7]
Output: [[3],[9,20],[15,7]]

Solution (Java):

public List<List<Integer>> levelOrder(TreeNode root) {
    List<List<Integer>> res = new ArrayList<>();
    if (root == null) return res;
    Queue<TreeNode> q = new ArrayDeque<>();
    q.add(root);
    while (!q.isEmpty()) {
        int sz = q.size();
        List<Integer> level = new ArrayList<>();
        for (int i = 0; i < sz; i++) {
            TreeNode n = q.poll();
            level.add(n.val);
            if (n.left != null) q.add(n.left);
            if (n.right != null) q.add(n.right);
        }
        res.add(level);
    }
    return res;
}

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

Question 6: two sum

Show solution

Problem Statement: Given an array of integers and a target, return indices of two numbers that add up to target.

Example:

Input: nums = [2, 7, 11, 15], target = 9
Output: [0, 1]

Solution (Java):

public int[] twoSum(int[] nums, int target) {
    Map<Integer, Integer> map = new HashMap<>();
    for (int i = 0; i < nums.length; i++) {
        int need = target - nums[i];
        if (map.containsKey(need)) return new int[]{map.get(need), i};
        map.put(nums[i], i);
    }
    return new int[]{};
}

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

Question 7: merge two sorted lists

Show solution

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 8

Q8: Worst-case time complexity of quicksort is?

Solution:

Unbalanced partitions (already sorted with bad pivot) → O(n²).

Answer: O(n²)

Question 9

Q9: Time complexity of binary search on a sorted array of n elements is?

Solution:

Each step halves the search space → O(log n).

Answer: O(log n)

Question 10

Q10: Which protocol is connection-oriented at the transport layer?

Solution:

TCP is connection-oriented; UDP is connectionless.

Answer: TCP

Question 11

Q11: Which SQL clause filters grouped rows after GROUP BY?

Solution:

HAVING filters aggregates; WHERE filters rows before grouping.

Answer: HAVING

Key insights from 2025 Paypal Online Assessment

Coding Section is Critical: Must solve 2-3 coding problems correctly to advance
Payment Security Focus: Strong emphasis on payment systems, transaction processing, security, AI-powered fraud detection
Time Management: 2-3 problems in 90 minutes requires excellent speed and accuracy
Success Rate: Only 10-15% cleared OA and advanced to interviews
Platform: PayPal’s assessment platform or HackerRank
Focus Areas: Arrays, trees, graphs, dynamic programming, payment systems, AI-powered security
Enhanced Emphasis: Optimal solutions, AI-powered fraud detection, and cloud-native payment systems

Paypal 2025 interview experiences

Based on recent candidate experiences from 2025 PayPal interviews:

2025 Interview Process:

Online Assessment (90 minutes): 2-3 coding problems
Technical Phone Screen (45-60 minutes): Coding problems, algorithm discussions, payment system concepts, AI/ML
Onsite/Virtual Interviews (4-5 rounds, 45-60 minutes each):

Coding rounds (2-3): Algorithms, data structures, problem-solving
System Design rounds: AI-powered payment systems, transaction processing, fraud detection, cloud-native security systems
Behavioral rounds: Problem-solving approach, security mindset, impact, AI/ML passion

2025 Interview Trends:

Increased emphasis on AI-powered fraud detection and cloud-native payment systems
More focus on optimal solutions and payment security best practices
Enhanced behavioral questions about security mindset and innovation
Questions about AI/ML applications in payment systems and fraud detection

Common 2025 Interview Topics:

Coding: Arrays, strings, trees, graphs, dynamic programming, payment algorithms, currency conversion
System Design: AI-powered payment systems, transaction processing, fraud detection, cloud-native security systems
Behavioral: Problem-solving, security mindset, teamwork, impact, AI/ML passion
PayPal Technologies: Payment systems, AI-powered features, transaction processing, cloud-native platforms

Success Tips:

Strong coding performance is essential - solve problems optimally
Understand payment systems, AI-powered fraud detection, and cloud-native payment systems
Practice system design for AI-powered payment systems and security
Prepare examples demonstrating problem-solving and security mindset
Learn PayPal’s products, AI features, and payment technologies
Practice explaining your thought process clearly

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

Preparation tips for Paypal 2025 pattern

Master Coding Fundamentals: Focus on solving 2-3 coding problems correctly - arrays, trees, graphs, DP
Payment System Expertise: Strong understanding of AI-powered payment systems, transaction processing, cloud-native security
Practice Previous Year Papers: Solve PayPal OA papers from 2020-2025 to understand evolving patterns
Time Management: Practice completing 2-3 coding problems in 90 minutes
LeetCode Practice: Solve 200+ LeetCode problems focusing on arrays, strings, trees, graphs (medium-hard difficulty)
Fintech Focus: Practice problems related to payment systems, transactions, AI/ML in fintech
System Design Mastery: Learn AI-powered payment system design, transaction processing, fraud detection, cloud-native architecture
Security Knowledge: Understand security best practices for payment systems and AI-powered fraud detection
Behavioral Preparation: Prepare examples using STAR format - problem-solving, security mindset, AI/ML passion
Mock Tests: Take timed practice tests to improve speed and accuracy
AI/ML in Fintech: Understand AI/ML applications in payment systems and fraud detection

Comments & Suggestions

2024 papers

Coding questions

Interview experience

Preparation guide

PayPal hub

Similar companies

Google · Amazon · Microsoft · Meta · Capital One · Goldman Sachs

Paypal Placement Papers 2025

Overview

Paypal Online Assessment 2025 pattern

Paypal Placement Papers 2025 - actual questions & solutions

Question 1: first non-repeating character

Question 2: valid parentheses

Question 3: reverse a string

Question 4: detect cycle in linked list

Question 5: binary tree level order

Question 6: two sum

Question 7: merge two sorted lists

Question 8

Question 9

Question 10

Question 11

Key insights from 2025 Paypal Online Assessment

Paypal 2025 interview experiences

Preparation tips for Paypal 2025 pattern

Comments & Suggestions

Related resources

Similar companies