Generally in any company 1st/2nd round will be problem solving round. I have make a list of all problem solving questions. 99% questions aksed will be part of this, interviewer might tweak the problem or combine the implementation of two problem.

For DSA, please follow Leetcode 100. Frontend Developer < 3 years of experince will be limited to Array, String, Linked List in most cases.

For Problem Solving, do practice the following problems.

• Implement deep cloning of an object
• Check if objects are deeply equal or not
• Reverse the string without reversing special char
• Flat deeply nested object with any special keyword
• Combine two sorted array in first array/new array
• Currying/ Infinite currying
• JSON.stringify with predefined delimeter
• JSON.parse with that delimeter used in JSON.stringify
• Implement Array flat function
• Polyfill for call/apply/bind
• Check for valid parentheses
• Check if object has cycle or not
• Polyfill for map/filter/reduce/forEach
• Polyfill for promise.all/any/race/allsettled
• Polyfill for setTimeout/clearTimeout
• Polyfill for setInterval/clearInterval
• Polyfill for splice/unshift

By following and practice thorough implementation of above problems, I can bet anyone can ace in PS/DS round.

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