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

SDE - Intern

ION
upvote
share-icon
2 rounds | 4 Coding problems

Interview preparation journey

expand-icon
Preparation
Duration: 3 months
Topics: Data Structures, Algorithms, OOPS, Dynamic Programming
Tip
Tip

Tip 1 : Practice popular questions from Arrays, Binary Trees, Linked Lists
Tip 2 : Make sure you are aware of calculating the time and space complexity for every problem you're coding.
Tip 3 : Prepare through Mock Interviews to practice explaining your approach while solving in an actual interview.

Application process
Where: Campus
Eligibility: 7 CGPA
Resume Tip
Resume tip

Tip 1 : Describe best of your projects in minimum words. Don't forget to add buzz words like REST APIs/ DB Indexing/ Benchmarking etc if you worked on backend.
Tip 2 : Don't add school achievements like Olympiads or Class Topper in your resume.
Tip 3 : If you've some work experience, put it in a way ,you're marketing yourself. Add terms like 'Created/Owned the Project through entire SDLC'
Tip 4 : Make sure you mention how your work experience actually impacted the company. Or how your self project can be actually useful to end user.

Interview rounds

01
Round
Medium
Video Call
Duration45 minutes
Interview date2 Nov 2021
Coding problem2

1. Square root (decimal)

Easy
10m average time
90% success
0/40
Asked in companies
UberVisaFacebook

You have been given two integers 'N' and 'D', Your task is to find the square root of the number 'N' with precision up to 'D' decimal places i.e. the difference between your answer and the correct answer should be less than 10 ^ (-D).

For example if N = 10 and D = 3, then your answer will be 3.162.

Problem approach

You have been given two integers 'N' and 'D', Your task is to find the square root of the number 'N' with precision up to 'D' decimal places i.e. the difference between your answer and the correct answer should be less than 10 ^ (-D).
For example if N = 10 and D = 3, then your answer will be 3.162.

Try solving now

2. Puzzle

3 Ants and Triangle
There are 3 ants sitting on three corners of a triangle. All ants randomly pick a direction and start moving along edge of the triangle. What is the probability that any two ants collide?

Problem approach

Collision doesn’t happen only in following two cases
1) All ants move in counterclockwise direction.
2) All ants move in clockwise direction.

Since every ant has two choices (pick either of two edges going through the corner on which ant is initially sitting), there are total 23 possibilities.
Out of 23 possibilities, only 2 don’t cause collision. So, the probability of collision is 6/8 and the probability of non-collision is 2/8.

02
Round
Medium
Video Call
Duration45 minutes
Interview date2 Nov 2022
Coding problem2

1. Puzzle

Heaven and Hell
There are two gates, one to hell and the other to heaven. Two gatekeepers, one for each gate. One of them always speaks the truth and the other always lies but you don’t know which one guards which gate. You are allowed only one question and you need to find out the gate to heaven.
What is the question?

Problem approach

Ask any guard “What would the other guard say if I ask which way is to the hell ?”
And whatever answer he give is the way to the heaven.
Explaintation:
If you end up asking the question to the truthful one, he will speak the truth and he knows that other guard is going to lie so he will show the way to the heaven.
If you end up asking the question to the liar, he will lie about the other and the answer will be the way to the heaven.

2. Puzzle

50 red marbles and 50 blue marbles
Give two boxes B1 and B2 one has 50 red marbles and the other has 50 blue marbles. A ball is selected randomly from any of the boxes and the task is to maximize the probability of selecting a red ball, by reshuffling marbles in both boxes.

Problem approach

Let P(R) be the probability of picking a red marble.

P(R) = P(B1) * P(B1 | J1) + P(B2) * P(B2 | J2)

Here, P(B1) and P(B2) refers to selecting B1 and B2 and the probability of selecting each box is \frac{1}{2} J1 and J2 refers to number of total balls in B1 and B2 respectively.



If we do not reshuffle any balls. Then

P(R) = ((1 / 2) * 1) + ((1 / 2) * 0) = 0.5

But, If we decrease the number of red balls in box B1 and increase the number of red balls in box B2 then the probability of getting a red ball will be maximized.
Therefore, let us take 49 red marbles from B1 to B2 then there will be 1 red ball in B1 and 99 balls in B2 out of which 49 are red and 50 of them are blue in the second jar.
Then

P (R) = ((1 / 2) * (1 / 1)) + ((1 / 2) * (49 / 99)) = 0.747474

Hence,

the maximum probability of choosing a red ball is 0.747474

Here's your problem of the day

Solving this problem will increase your chance to get selected in this company

Skill covered: Programming

What is recursion?

Choose another skill to practice
Similar interview experiences
company logo
SDE - 1
2 rounds | 4 problems
Interviewed by ION
0 views
0 comments
0 upvotes
company logo
SDE - 1
2 rounds | 4 problems
Interviewed by ION
756 views
0 comments
0 upvotes
company logo
SDE - 1
2 rounds | 4 problems
Interviewed by ION
1464 views
0 comments
0 upvotes
company logo
SDE - Intern
3 rounds | 5 problems
Interviewed by ION
829 views
0 comments
0 upvotes
Companies with similar interview experiences
company logo
SDE - Intern
3 rounds | 6 problems
Interviewed by Amazon
15480 views
4 comments
0 upvotes
company logo
SDE - Intern
4 rounds | 7 problems
Interviewed by Microsoft
15338 views
1 comments
0 upvotes
company logo
SDE - Intern
2 rounds | 4 problems
Interviewed by Amazon
10142 views
2 comments
0 upvotes