Solutions

Meeting Rooms Easy Meeting Rooms II Medium Meeting Rooms III Hard Divide Intervals Into Minimum Number of Groups Medium Remove Covered Intervals Medium Minimum Number of Arrows to Burst Balloons Medium The Number of the Smallest Unoccupied Chair Medium Check if Grid can be Cut into Sections Medium My Calendar I Medium My Calendar II Medium Count Days Without Meetings Medium Minimum Interval to Include Each Query Hard Data Stream as Disjoint Intervals Hard

Math & Geometry

Excel Sheet Column Title Easy Greatest Common Divisor of Strings Easy Insert Greatest Common Divisors in Linked List Medium Count Odd Numbers in an Interval Range Easy Matrix Diagonal Sum Easy Calculate Money in Leetcode Bank Easy Largest Odd Number in String Easy Transpose Matrix Easy Image Smoother Easy Count of Matches in Tournament Easy Water Bottles Easy Largest Local Values in a Matrix Easy Power of Four Easy Lucky Numbers in a Matrix Easy Maximum Points on a Line Hard Magic Squares In Grid Medium Rotate Image Medium Spiral Matrix Medium Spiral Matrix II Medium Spiral Matrix III Medium Spiral Matrix IV Medium Set Matrix Zeroes Medium Happy Number Easy Plus One Easy Palindrome Number Easy Ugly Number Easy Convert 1D Array Into 2D Array Easy Shift 2D Grid Easy Roman to Integer Easy Integer to Roman Medium Pow(x, n) Medium Find the Punishment Number of an Integer Medium Check if Number is a Sum of Powers of Three Medium Multiply Strings Medium Detect Squares Medium Robot Bounded In Circle Medium Walking Robot Simulation Medium Zigzag Conversion Medium Rotating the Box Medium Sum of Square Numbers Medium Find Missing Observations Medium Minimum Time Difference Medium Minimum Operations to Make a Uni-Value Grid Medium Largest Submatrix With Rearrangements Medium Wildest Vertical Area Between Two Points Containing No Points Easy Tuple with Same Product Medium Lexicographical Numbers Medium Find the Winner of the Circular Game Medium Count Total Number of Colored Cells Medium Prime Subtraction Operation Medium Closest Prime Numbers in Range Medium Minimum Number of One Bit Operations to Make Integers Zero Hard K-th Smallest in Lexicographical Order Hard Integer to English Words Hard

Bit Manipulation

Single Number Easy Single Number III Medium Number of 1 Bits Easy Counting Bits Easy Add Binary Easy Minimum Bit Flips to Convert Number Easy Reverse Bits Easy Missing Number Easy Shuffle the Array Easy Add to Array-Form of Integer Easy Find the Difference Easy Power of Two Easy Sum of Two Integers Medium Reverse Integer Medium Bitwise XOR of All Pairings Medium Largest Combination With Bitwise AND Greater Than Zero Medium XOR Queries of a Subarray Medium Maximum XOR for Each Query Medium Neighboring Bitwise XOR Medium Shortest Subarray With OR at Least K II Medium Bitwise AND of Numbers Range Medium Find Kth Bit in Nth Binary String Medium Count Triplets That Can Form Two Arrays of Equal XOR Medium Minimum Array End Medium Find if Array Can Be Sorted Medium Longest Subarray With Maximum Bitwise AND Medium Longest Nice Subarray Medium Find the Longest Substring Containing Vowels in Even Counts Medium Minimize XOR Medium

JavaScript

Create Hello World Function Easy Counter Easy Counter II Easy Apply Transform over each Element in Array Easy Filter Elements from Array Easy Array Reduce Transformation Easy Function Composition Easy Allow One Function Call Easy Memoize Medium Curry Medium Sleep Easy Promise Time Limit Easy Promise Pool Medium Cache With Time Limit Medium Debounce Medium Throttle Medium JSON Deep Equal Medium Convert Object to JSON String Medium Array of Objects to Matrix Medium Difference Between Two Objects Medium Chunk Array Easy Flatten Deeply Nested Array Medium Array Prototype Last Easy Group By Medium Check if Object Instance of Class Medium Call Function with Custom Context Medium Event Emitter Medium Array Wrapper Easy Generate Fibonacci Sequence Easy Nested Array Generator Medium

2620. Counter - Explanation

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