# Walmart Lab Interview Experience | Set 8 (Off-Campus 3 Years Experience)

**Round 1 (Coding round):**

1) Range [L, R] is given. Need to find what is the maximum repeating digit in prime numbers between L and R (both inclusive). If more number of digits is repeated max times, return whichever digit is maximum

Eg: [2, 13] – maximum repeating digit is 1 among {2, 3, 5, 7, 11, 13}

[2, 9] – answer 7

2) Given a number “S”, find out how many number of ways a, b, c, d (all > 1) can exist such that a+b+c+d = S;

**Round 2:**

1) OOPS Concepts

2) Reverse alternate nodes in linked list

Eg: 1->2->3->4->5 ahould become 2->1->4->3->5

3) Iterative post order traversal of binary tree

4) Queue implementation using stacks

**Round 3 (Java):**

1) Arraylist, Linkedlist – when to use what

2) Hashmap, Hashtable, concurrent hash map

3) Hashcode, Equals, Hashmap implementation

4) Serializable interface

5) AbstractClass Vs Interface

6) Multi threading, Difference between extends thread, implements runnable

7) Callable interface, Executor framework

8) Collections sorting, comparable interface

9) Best thing I have done so far what I proud of

**Round 4:**

1) Given NxN matrix, (X,Y) position. Find how many ways You can reach from (X,Y) to (N,N). You are allowed to traverse in 2 directions – Right, Down

2) Find loop in linked list. Find starting node of loop

3) Binary tree zigzag traversal

4) Given list of stock prices. You are allowed to buy and sell only once.

a) Find the maximum gain you can get

b) Find the maximum loss you can get

5) Binary tree is height balanced or not. (Every node in tree should be height balanced)

6) Implement String trim algorithm

7) Write a multi-threaded program – launch 10 threads and exit from main thread after all those threads completed

**Round 5 (Manager):**

1) Given a number in form of array, maximize the number w.r.t allowed number of swaps (can swap only adjacent elements) – maximize(int[] data, int numSwaps)

Eg: 1265 is number – if 1 swap allowed – maximum number we can get out of it is 2165

1265 is number – if 3 swaps allowed – maximum number we can get out of it is 6215

2) Questions on my projects

3) So many behavioural questions

**Round 6 (HR):**

Why do you want to change? What You are expecting? and some other HR questions.

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## Related Practice Problems

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