DSA Solutions - Page 75

Each solution breaks the problem into approaches, usually from brute force to the best one, and explains why each works. Code comes in Python, Java, C++ and other languages. Knowing why an approach works matters more in an interview than remembering the code.

Try the problem first. Give it at least 20 minutes before you open the solution.
Read every approach. The brute force shows you the problem; the faster ones show the pattern.
Check the complexity. Note the time and space of each approach and what makes the difference.
Write it yourself. Close the solution and code it from memory in the editor.
Come back in a week. Solving it again later is what makes the pattern stick.

All problems Topics Company questions Sheets

Solutions, explained

3816.Lexicographically Smallest String After Deleting Duplicate Characters

3817.Good Indices in a Digit String

3818.Minimum Prefix Removal to Make Array Strictly Increasing

3819.Rotate Non Negative Elements

3820.Pythagorean Distance Nodes in a Tree

3821.Find Nth Smallest Integer With K One Bits

3822.Design Order Management System

3823.Reverse Letters Then Special Characters in a String

3824.Minimum K to Reduce Array Within Limit

3825.Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND

3827.Count Monobit Integers

3828.Final Element After Subarray Deletions

3829.Design Ride Sharing System

3830.Longest Alternating Subarray After Removing At Most One Element

3831.Median of a Binary Search Tree Level

3832.Find Users with Persistent Behavior Patterns

3833.Count Dominant Indices

3834.Merge Adjacent Equal Elements

3835.Count Subarrays With Cost Less Than or Equal to K

3836.Maximum Score Using Exactly K Pairs

3837.Delayed Count of Equal Elements

3838.Weighted Word Mapping

3839.Number of Prefix Connected Groups

3840.House Robber V

3841.Palindromic Path Queries in a Tree

3842.Toggle Light Bulbs

3843.First Element with Unique Frequency

3844.Longest Almost-Palindromic Substring

3845.Maximum Subarray XOR with Bounded Range

3846.Total Distance to Type a String Using One Finger

3847.Find the Score Difference in a Game

3848.Check Digitorial Permutation

3849.Maximum Bitwise XOR After Rearrangement

3850.Count Sequences to K

3851.Maximum Requests Without Violating the Limit

3852.Smallest Pair With Different Frequencies

3853.Merge Close Characters

3854.Minimum Operations to Make Array Parity Alternating

3855.Sum of K-Digit Numbers in a Range

3856.Trim Trailing Vowels

3857.Minimum Cost to Split into Ones

3858.Minimum Bitwise OR From Grid

3859.Count Subarrays With K Distinct Integers

3860.Unique Email Groups

3861.Minimum Capacity Box

3862.Find the Smallest Balanced Index

3863.Minimum Operations to Sort a String

3864.Minimum Cost to Partition a Binary String

3865.Reverse K Subarrays

3866.First Unique Even Element

How to use these solutions