EPAM Systems Interview Experience

You are given an array 'arr' having 'n' distinct integers sorted in ascending order. The array is right rotated 'r' times Find the minimum value of 'r'. Right rotating an array means shifting the element at 'ith' index to (‘i+1') mod 'n' index, for all 'i' from 0 to ‘n-1'. Example: Input: 'n' = 5 , ‘arr’ = [3, 4, 5, 1, 2] Output: 3 Explanation: If we rotate the array [1 ,2, 3, 4, 5] right '3' times then we will get the 'arr'. Thus 'r' = 3. Input format: The first line contains an integer ‘n’, representing the size of the array ‘arr’. The second line contains ‘n’ integers, elements of ‘arr’. Output Format: Return an integer, value of ‘r’. Note: You don’t need to print anything, it has already been taken care of, just complete the given function.

You are given two strings, s1 and s2, which are guaranteed to be of the same length. Your task is to compare these two strings character by character and identify all the positions (indices) where they differ. You need to return a list of these 0-indexed positions. Input Format: The first line of input contains the string s1. The second line of input contains the string s2. Output Format: Print a single line containing the 0-indexed positions where the characters differ, sorted in ascending order and separated by single spaces. If the two strings are identical (no mismatches), print a single line with the value -1. Note: The comparison is case-sensitive. 'a' and 'A' are considered different. The strings are guaranteed to have the same length.

Design and implement a data structure for Least Recently Used (LRU) cache to support the following operations: 1. get(key) - Return the value of the key if the key exists in the cache, otherwise return -1. 2. put(key, value), Insert the value in the cache if the key is not already present or update the value of the given key if the key is already present. When the cache reaches its capacity, it should invalidate the least recently used item before inserting the new item. You will be given ‘Q’ queries. Each query will belong to one of these two types: Type 0: for get(key) operation. Type 1: for put(key, value) operation. Note : 1. The cache is initialized with a capacity (the maximum number of unique keys it can hold at a time). 2. Access to an item or key is defined as a get or a put operation on the key. The least recently used key is the one with the oldest access time. Input Format : The first line of input contains two space-separated integers 'C' and 'Q', denoting the capacity of the cache and the number of operations to be performed respectively. The next Q lines contain operations, one per line. Each operation starts with an integer which represents the type of operation. If it is 0, then it is of the first type and is followed by one integer key. If it is 1, it is of the second type and is followed by two space-separated integers key and value(in this order). Output Format : For each operation of type 0, print an integer on a single line, denoting the value of the key if the key exists, otherwise -1. Note : You don't need to print anything, it has already been taken care of. Just implement the given function. Constraints : 1 <= C <= 10^4 1 <= Q <= 10^5 1 <= key, value <= 10^9 Time Limit: 1 sec Sample Input 1 : 3 11 1 1 1 1 2 2 1 3 3 1 4 5 0 3 0 1 0 4 1 2 3 0 1 0 3 0 2 Sample Output 1 : 3 -1 5 -1 3 3 Explanation to Sample Input 1 : Initializing a cache of capacity 3, LRUCache cache = new LRUCache(3); Then each operation is performed as shown in the above figure. cache.put(1,1) cache.put(2,2) cache.put(3,3) cache.put(4,5) cache.get(3) // returns 3 cache.get(1) // returns -1 cache.get(2) // returns 2 cache.put(5,5) cache.get(4) // returns -1 cache.get(3) // returns 3 Sample Input 2 : 2 6 1 1 1 1 2 2 0 2 1 3 3 0 3 0 1 Sample Output 2 : 2 3 -1

How do you get a lion, a goat, and a cabbage across a river using a single-passenger boat without any of them eating each other?

You are given a sorted integer array 'arr' of size 'n' . You need to remove the duplicates from the array such that each element appears only once. Return the length of this new array. Note: Do not allocate extra space for another array. You need to do this by modifying the given input array in place with O(1) extra memory. For example: 'n' = 5, 'arr' = [1 2 2 2 3]. The new array will be [1 2 3]. So our answer is 3. Input format: The first line contains an integer ‘n’ denoting the number of elements in the array. The second line contains ‘n’ space-separated integers representing the elements of the array. Output format: Return the length of the modified array. Note: You don't need to print anything, it has already been taken care of. Just Implement the given function.

The interviewer started by asking about my project and the problem I was trying to solve. They asked how I use AI in my daily life. They also asked how I would approach the problem of finding the population of Kanpur.

I was rejected because I was unable to answer some technical questions and got a bit confused while solving the puzzles.

Key Preparation Tips

Prepare DSA thoroughly.

Practice aptitude and puzzle-based questions.

Have at least two good projects on your resume.

Be prepared to explain your projects clearly.

Practice coding problems involving Arrays, Binary Search, DP and Recursion.

Prepare common HR questions such as Tell me about yourself and Who is your role model?