Top 20 Puzzles commonly asked during the SDE interviews - Study24x7
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Top 20 Puzzles commonly asked during the SDE interviews

Updated on 02 December 2022
Akshay Sharma
23 min read 43 views
Updated on 02 December 2022

How to prepare for SDE interviews? Are there any puzzles that help to become well prepared for SED interviews? Puzzles are one of the unique ways to evaluate problem-solving skills. Puzzles are like tough questions that allow you to think in a logical way. 

Puzzles can be either a toy, question or a riddle which are used to test the wickedness and knowledge of a person. To answer the puzzles, you should be focused and stay aware of certain conditions. It proves you calmly behave in pressure situations.

This is why we outline the top 20 puzzles interview questions generally asked by leading companies like Microsoft, Amazon, etc. The process of solving the puzzles does not provide you with good logical ability because nobody has an idea of what will be asked in SDE interviews. Thusl, the given list of standard Puzzles will surely help you in SDE interviews.

Some Common Puzzle Examples

1. 3 ants and a triangle

3 ants are sitting on 3 corners of the triangle. All ants choose their random direction and begin to move along the edge of the triangle. What is the chance of collision between two ants?

2. Heaven & Hell

Two gates are there, one goes to hell, and the other goes to heaven. Two gatekeepers are hired for two different gates, in which one speaks the truth, and the other speaks lies. But we need to determine which guard is telling the truth or lies.

According to this interview puzzle, you have only one permit to ask a question to both the keepers and find the gate to heaven based on their answers. What will be the question that you will ask to the keepers ? Find the question by solving this puzzle, and become ready for aptitude preparation.

3. 10 coin puzzles

You are kept blindfolded, and a total of 10 coins are placed in front of you. You can touch the coins but cannot tell which coins give you which feel. You only know that there are 5 coins heads and 5 coins tails, but which one is the head or which one is a tale; you do not know. Can you make two coin piles with the same head numbers?

4. Mislabeled Jars

There are a total of 3 mislabeled jars, A, B, and C. You are only allowed to put your hand in the jar and get one eater at a time. Say the least number of eateries in aptitude preparation that you need to pick to label the different jars correctly.

5. 50 blue marbles and 50 red marbles

There are two boxes in interview puzzles, B1 and B2, one contains 50 red marbles, and the other contains 50 blue marbles. By reshuffling, you have to select the ball from boxes and increase the chance of choosing red marbles.

6. Minimum cut puzzles

You can hire someone for five days for your work and pay them the gold bars every day. What are some numbers of cuts to the gold bars that permit you to pay 1/5th every day?

7. 100 doors

There are 100 doors, all of them are closed. Person tried to walk through all given doors and toggle them. Which doors are open at the end of the process?

8. Find the quick 3 horses

You have to find 3 horses from the available 20 horses total. You have to conduct the horse race between at most 5 horses, to check their speed. How many races need to be conducted to find 3 fast horses in this interview puzzle?

9. Compute the overall distance by bee travelling

Two trains are coming towards each other at a fast speed. Then, bees are suddenly coming between the two trains when they are 100 km away. How much distance does a bee travel in total?

10. 3 cuts need to cut the cake into 8 pieces equally

You have to cut your birthday cake into 8 equal pieces with only 3 cuts. How can you do it?

11. Explore the last ball after the whole process

There are 16 blue balls and 20 red balls in the bag. Randomly any 2 balls are removed at every step and replaced with a new ball. Find the last ball in the bag that remains after the complete process.

12. The two water jug

You have first to empty the jug, fill the jug, then transfer the water from one jug to another until any of the jugs is completely filled or empty.

13. 3 switches and 3 bulbs

A room has three light bulbs, and these bulbs are connected to three switches. You have to identify every switch with bulbs and determine whether all bulbs work properly.

14. How to measure forty-five minutes with two same wires

How to measure 45 minutes with two same wires, in which every wire might take time of 1 hour to burn? The wires burn in a non-uniform way according to the interview puzzles.

15. Find the daughter's age

Ram has three daughters, and his friend gave him the idea to find the daughters' ages by sum and product of their ages with house numbers. The oldest girl of Ram appeared like strawberry ice cream.

16. 10 balls in five lines

There are 10 balls, and you have to keep 10 balls on 5 lines in such a way that every line consists of the 4 balls precisely.

17. Pay an employee with a gold rod of 7 units

An employee works under the employer for a week. The employer owns 7 units of gold rod. How does the employer pay to employees, so that the rod units of employees are increased by the end of every work day? This puzzle also helps you to become ready for aptitude preparation.

18. Bridge and torch

4 people are there, A, B, C, and D who have to cross the bridge at night. Person A takes one minute, B takes 2 minutes, C takes 5 minutes, and D takes 8 minutes to cross the bridge at night.

19. Poison & rat

This interview puzzle is based on the 1000 wine bottles. One bottle in these consists of poisoned wine. One of the rats dies after 1 hour of drinking this poisoned wine. How many rats are required to find the number of poisoned bottles.

20. Banana and camel puzzle

A person carries 3000 camels and bananas. The person has to transport the maximum bananas to a destination that is 1000 Kms away, with the help of camels as the transportation mode.

But the camels cannot carry more than 1000 bananas simultaneously and also eat bananas after covering the 1km of travel. How many bananas are transferred to the destination by using one camel?


You can practise these puzzles and ace them in no time. Hope all the above interview puzzles will help you pass the SDE interviews with flying colours! 

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