Okcredit interview experience Real time questions & tips from candidates to crack your interview

Backend developer intern

Okcredit

2 rounds | 5 Coding problems

vidya gupta

Fresher | Nov 2021

Rejected

Interview preparation journey

Preparation

Duration: 5 months

Topics: OOPS, System Design, Algorithms, Data Structures, DBMS

Tip

Tip 1 : Prepare System Design
Tip 2 : Practice DSA Questions properly
Tip 3 : Practice OOPS and DBMS Concepts

Application process

Where: Referral

Eligibility: Above 7 CGPA, Good Problem Solving Skills

Resume tip

Tip 1 : Your Resume should consist mainly of skills, projects, and achievements. Projects would play a crucial part in your interview and you should have at least one most relevant and good project that shows how strong your concepts are in development.
Tip 2 : The most important tip is that never lie on your resume If you have worked upon some technology for the project part only and don't know the proper depth you could write basics only in your resume.

Interview rounds

Round

Medium

Video Call

Duration60 minutes

Interview date29 Nov 2021

Coding problem2

This round was conducted on Google meet. It was conducted at 5:30 Pm. Interviewer was very polite and helpful. he helped me wherever i got stuck.

1. Palindrome Partitioning

Moderate

25m average time

75% success

0/80

Asked in companies

You are given a string 'S'. Your task is to partition 'S' such that every substring of the partition is a palindrome. You need to return all possible palindrome partitioning of 'S'.

Note: A substring is a contiguous segment of a string.

For Example:

For a given string “BaaB”
3 possible palindrome partitioning of the given string are:
{“B”, “a”, “a”, “B”}
{“B”, “aa”, “B”}
{“BaaB”}
Every substring of all the above partitions of “BaaB” is a palindrome.

Problem approach

loop through the string, check if substr(0, i) is palindrome. If it is, recursively call dfs() on the rest of sub string: substr(i+1, length). keep the current palindrome partition so far in the 'path' argument of dfs(). When reaching the end of string, add current partition in the result.

Try solving now

2. Palindrome Partitioning ll

Hard

40m average time

60% success

0/120

Asked in companies

You are given a string 'str' of length 'n'.

Find the minimum number of partitions in the string so that no partition is empty and every partitioned substring is a palindrome.

Example :

Input: 'str' = "aaccb"

Output: 2

Explanation: We can make a valid partition like aa | cc | b.

Problem approach

This can be solved by two points:

cut[i] is the minimum of cut[j - 1] + 1 (j <= i), if [j, i] is palindrome.
If [j, i] is palindrome, [j + 1, i - 1] is palindrome, and c[j] == c[i].
The 2nd point reminds us of using dp (caching).

Try solving now

Round

Medium

Video Call

Duration60 minutes

Interview date3 Dec 2021

Coding problem3

This round was taken by a technical lead. He started by asking os and networking problems. then switched to projects in which he asked a lot of questions followed by 1 dsa problem.

1. Operating System Questions

What is a deadlock?
Explain Banker's Algorithm

Problem approach

Tip 1 : Prepare most common questions
Tip 2 : Explain your thought process and use google doc if required

2. Add Two Numbers As Linked Lists

Moderate

20m average time

80% success

0/80

Asked in companies

You are given two non-negative numbers 'num1' and 'num2' represented in the form of linked lists.

The digits in the linked lists are stored in reverse order, i.e. starting from least significant digit (LSD) to the most significant digit (MSD), and each of their nodes contains a single digit.

Calculate the sum of the two numbers and return the head of the sum list.

Example :

Input:
'num1' : 1 -> 2 -> 3 -> NULL
'num2' : 4 -> 5 -> 6 -> NULL

Output: 5 -> 7 -> 9 -> NULL

Explanation: 'num1' represents the number 321 and 'num2' represents 654. Their sum is 975.

Problem approach

we can just use set.insert(key).second to check but it will take up O(n) space which is quite an awful waste, so here we just going to check the circle and then locate it.

If there is a circle then once the slow meets the fast the first time, there will be a formula as follows: a+b+kl = 2(a+b) -> kl-b = a (a is the length between the head and the start of the circle, b is the steps the slow pointer moves in the circle while l is the length of the circle).
After that we can reset the fast and slow down the fast (same speed as the slow using kl-b = a) then once they meet again, the location will be the start of the circle.
At last we take up constant space to solve this and traverse the linked list twice at most (as for the slow pointer).

Try solving now

3. Multiply Linked Lists

Easy

15m average time

85% success

0/40

Asked in companies

Given two numbers represented by linked lists. Your task is to find the multiplied list and return the head of the multiplied list.

The multiplied list is a linked list representation of the multiplication of two numbers.

Problem approach

1) Initialize a variable to zero
2) Start traversing the linked list
3) Add the value of first node to this variable
4) From the second node, multiply the variable by 10
and also take modulus of this value by 10^9+7
and then add the value of the node to this
variable.
5) Repeat step 4 until we reach the last node of the list.

Try solving now