LeetCode Solutions

#1 Easy

Two Sum

Complete solution for LeetCode Two Sum problem with efficient algorithms, multiple approaches, and code implementations in C++, Java, and Python.

#1290 Easy

Convert Binary Number in a Linked List to Integer

Convert a binary number represented as a linked list (with each node containing 0 or 1) to its equivalent decimal integer.

#1295 Easy

Find Numbers with Even Number of Digits

Count numbers which has even number of digits.

#1920 Easy

Build Array from Permutation

You will learn in-place array transformations.

#1957 Easy

Delete Characters to Make Fancy String

Learn the optimal solution for LeetCode 1957: Delete minimum characters to prevent three consecutive identical characters. Code Implementations included.

#2094 Easy

Finding 3-Digit Even Numbers

Efficient approaches to find all unique 3-digit even numbers from digits.

#2138 Easy

Divide a String Into Groups of Size k

Multiple approaches including Substring with Padding, Two-Pointer Technique, Iterative Character Collection, and Mathematical Grouping with C++, Java, Python.

#3024 Easy

Type of Triangle

Determine triangle type using multiple approaches including direct comparison, sorting optimization, and set-based type detection.

#3136 Easy

Valid Word

Complete solution for LeetCode 3136 Valid Word problem with multiple approaches, detailed explanations, and code implementations.

#3392 Easy

Count Subarrays of Length Three With Condition

Count subarrays where sum of first and third elements equals half of the second element.

#3432 Easy

Count Partitions with Even Sum Difference

Count when sum of the left and right subarrays is even.

#3442 Easy

Maximum Difference Between Even and Odd Frequency I

Efficient approaches to find maximum difference between even and odd character frequencies in strings, including optimized single-pass methods.

#3487 Easy

Maximum Unique Subarray Sum After Deletion

Optimal O(n) solution with distinct positives approach. Learn multiple methods to solve the maximum unique subarray sum problem after deletion.

#3536 Easy

Maximum Product of Two Digits

Maximum Product using digit extraction and sorting.

#3541 Easy

Find Most Frequent Vowel and Consonant

Discover optimal methods to find maximum vowel and consonant frequencies.

#3545 Easy

Minimum Deletions for At Most K Distinct Characters

Learn optimal strategies to minimize deletions while maintaining character diversity.

#3550 Easy

Smallest Index With Digit Sum Equal to Index

Multiple approaches like Modulo Division, String Conversion Method, Precomputed Digit Sums.

#3591 Easy

Check if Any Element Has Prime Frequency

Multiple approaches to check if any array element has prime frequency using Frequency Map, Frequency Array with Prime Precomputation, Set of Prime Frequencies.

#3622 Easy

Check Divisibility by Digit Sum and Product

Learn efficient digit extraction techniques and multiple approaches to solve divisibility problems with detailed implementations.

#73 Medium

Set Matrix Zeroes

Efficient approaches to set matrix zeroes in-place including O(1) space optimization and various implementation methods.

#838 Medium

Push Dominoes

Two efficient approaches: Force Propagation and BFS Simulation.

#898 Medium

Bitwise ORs of Subarrays

Efficient O(n log max) solution using dynamic programming with sets.

#1432 Medium

Max Difference You Can Get From Changing an Integer

Efficient approaches to find maximum difference from digit replacement operations, including greedy algorithms and optimized methods.

#1695 Medium

Maximum Erasure Value

LeetCode 1695: Maximum Erasure Value using sliding window and prefix sum techniques. Detailed explanations and implementations.

#1829 Medium

Maximum XOR for Each Query

Find the maximum XOR result for each query on an array.

#2419 Medium

Longest Subarray With Maximum Bitwise AND

Learn multiple methods to solve the maximum bitwise AND subarray problem with detailed implementations.

#2799 Medium

Count Complete Subarrays in an Array

Count how many subarrays contain all distinct elements present in the original array.

#2918 Medium

Minimum Equal Sum of Two Arrays After Replacing Zeros

Learn optimal strategies to balance array sums by replacing zeros.

#2962 Medium

Count Subarrays Where Max Element Appears at Least K Times

Count all subarrays where the maximum element appears at least k times

#3223 Medium

Minimum Length of String After Operations

Find the minimum possible length of string after performing operations.

#3387 Medium

Maximize Amount After Two Days of Conversions

This problem requires understanding of graph algorithms and dynamic programming.

#3335 Medium

Total Characters in String After Transformations I

Efficient approaches to calculate string length after transformations using frequency mapping and mathematical optimization.

#3546 Medium

Equal Sum Grid Partition I

Learn efficient methods to partition grids into equal sums.

#3551 Medium

Minimum Swaps to Sort by Digit Sum

Efficient approaches to calculate minimum swaps for digit-sum sorting using cycle detection and custom comparators.

#3566 Medium

Partition Array into Two Equal Product Subsets

Efficient approaches to partition an array into two subsets with equal product, including prime factorization and bitmasking techniques.

#3587 Medium

Minimum Adjacent Swaps to Alternate Parity

LeetCode 3587 with efficient algorithms, multiple approaches, and code implementations in C++, Java, and Python.

#3618 Medium

Split Array by Prime Indices

Learn efficient prime identification techniques and multiple approaches to solve the array splitting problem.

#3619 Medium

Count Islands With Total Value Divisible by K

Learn efficient island counting techniques using DFS, BFS, and iterative methods with detailed implementations.

#3537 Medium

Fill a Special Grid

Construct a 2N x 2N grid where each quadrant follows strict ordering rules recursively.

#2302 Hard

Count Subarrays With Score Less Than K

Count all the subarrays where product of sum and length is less than k