Simulation LeetCode Problems: All 144, With Python Solutions

Every problem in this library that LeetCode tags Simulation — 144 in total, 132 of them with a complete Python solution, a worked example and the time and space complexity of the approach.

144 problems
57 Easy
77 Medium
10 Hard

Simulation problems by difficulty

Problems with a complete Python solution are listed first, then by ascending problem number.

Easy (57)

#	Problem	Difficulty	Topics
67	Add Binary	Easy	Bit Manipulation, Math, String +1
258	Add Digits	Easy	Math, Number Theory, Simulation
412	Fizz Buzz	Easy	Math, String, Simulation
415	Add Strings	Easy	Math, String, Simulation
495	Teemo Attacking	Easy	Array, Simulation
566	Reshape the Matrix	Easy	Array, Matrix, Simulation
657	Robot Return to Origin	Easy	String, Simulation
682	Baseball Game	Easy	Stack, Array, Simulation
832	Flipping an Image	Easy	Bit Manipulation, Array, Two Pointers +2
844	Backspace String Compare	Easy	Stack, Two Pointers, String +1
867	Transpose Matrix	Easy	Array, Matrix, Simulation
999	Available Captures for Rook	Easy	Array, Matrix, Simulation
1103	Distribute Candies to People	Easy	Math, Simulation
1252	Cells with Odd Values in a Matrix	Easy	Array, Math, Simulation
1260	Shift 2D Grid	Easy	Array, Matrix, Simulation
1275	Find Winner on a Tic Tac Toe Game	Easy	Array, Hash Table, Matrix +1
1389	Create Target Array in the Given Order	Easy	Array, Simulation
1518	Water Bottles	Easy	Math, Simulation
1560	Most Visited Sector in a Circular Track	Easy	Array, Simulation
1603	Design Parking System	Easy	Design, Counting, Simulation
1646	Get Maximum in Generated Array	Easy	Array, Simulation
1688	Count of Matches in Tournament	Easy	Math, Simulation
1700	Number of Students Unable to Eat Lunch	Easy	Stack, Queue, Array +1
1920	Build Array from Permutation	Easy	Array, Simulation
1929	Concatenation of Array	Easy	Array, Simulation
1945	Sum of Digits of String After Convert	Easy	String, Simulation
2011	Final Value of Variable After Performing Operations	Easy	Array, String, Simulation
2022	Convert 1D Array Into 2D Array	Easy	Array, Matrix, Simulation
2073	Time Needed to Buy Tickets	Easy	Queue, Array, Simulation
2138	Divide a String Into Groups of Size k	Easy	String, Simulation
2154	Keep Multiplying Found Values by Two	Easy	Array, Hash Table, Sorting +1
2169	Count Operations to Obtain Zero	Easy	Math, Simulation
2180	Count Integers With Even Digit Sum	Easy	Math, Simulation
2243	Calculate Digit Sum of a String	Easy	String, Simulation
2293	Min Max Game	Easy	Array, Simulation
2303	Calculate Amount Paid in Taxes	Easy	Array, Simulation
2357	Make Array Zero by Subtracting Equal Amounts	Easy	Greedy, Array, Hash Table +3
2460	Apply Operations to an Array	Easy	Array, Two Pointers, Simulation
2500	Delete Greatest Value in Each Row	Easy	Array, Matrix, Sorting +2
2549	Count Distinct Numbers on Board	Easy	Array, Hash Table, Math +1
2553	Separate the Digits in an Array	Easy	Array, Simulation
2558	Take Gifts From the Richest Pile	Easy	Array, Simulation, Heap (Priority Queue)
2562	Find the Array Concatenation Value	Easy	Array, Two Pointers, Simulation
2582	Pass the Pillow	Easy	Math, Simulation
2660	Determine the Winner of a Bowling Game	Easy	Array, Simulation
2682	Find the Losers of the Circular Game	Easy	Array, Hash Table, Simulation
2696	Minimum String Length After Removing Substrings	Easy	Stack, String, Simulation
2717	Semi-Ordered Permutation	Easy	Array, Simulation
2739	Total Distance Traveled	Easy	Math, Simulation
2744	Find Maximum Number of String Pairs	Easy	Array, Hash Table, String +1
2810	Faulty Keyboard	Easy	String, Simulation
2899	Last Visited Integers	Easy	Array, Simulation
2946	Matrix Similarity After Cyclic Shifts	Easy	Array, Math, Matrix +1
2960	Count Tested Devices After Test Operations	Easy	Array, Counting, Simulation
2974	Minimum Number Game	Easy	Array, Sorting, Simulation +1
157	Read N Characters Given Read4Premium	Easy	Array, Interactive, Simulation
1243	Array TransformationPremium	Easy	Array, Simulation

Medium (77)

#	Problem	Difficulty	Topics
43	Multiply Strings	Medium	Math, String, Simulation
54	Spiral Matrix	Medium	Array, Matrix, Simulation
59	Spiral Matrix II	Medium	Array, Matrix, Simulation
289	Game of Life	Medium	Array, Matrix, Simulation
498	Diagonal Traverse	Medium	Array, Matrix, Simulation
537	Complex Number Multiplication	Medium	Math, String, Simulation
592	Fraction Addition and Subtraction	Medium	Math, String, Simulation
640	Solve the Equation	Medium	Math, String, Simulation
735	Asteroid Collision	Medium	Stack, Array, Simulation
874	Walking Robot Simulation	Medium	Array, Hash Table, Simulation
885	Spiral Matrix III	Medium	Array, Matrix, Simulation
946	Validate Stack Sequences	Medium	Stack, Array, Simulation
950	Reveal Cards In Increasing Order	Medium	Queue, Array, Sorting +1
985	Sum of Even Numbers After Queries	Medium	Array, Simulation
1006	Clumsy Factorial	Medium	Stack, Math, Simulation
1041	Robot Bounded In Circle	Medium	Math, String, Simulation
1094	Car Pooling	Medium	Array, Prefix Sum, Sorting +2
1222	Queens That Can Attack the King	Medium	Array, Matrix, Simulation
1324	Print Words Vertically	Medium	Array, String, Simulation
1404	Number of Steps to Reduce a Number in Binary Representation to One	Medium	Bit Manipulation, String, Simulation
1409	Queries on a Permutation With Key	Medium	Binary Indexed Tree, Array, Simulation
1441	Build an Array With Stack Operations	Medium	Stack, Array, Simulation
1503	Last Moment Before All Ants Fall Out of a Plank	Medium	Brainteaser, Array, Simulation
1535	Find the Winner of an Array Game	Medium	Array, Simulation
1545	Find Kth Bit in Nth Binary String	Medium	Recursion, String, Simulation
1562	Find Latest Group of Size M	Medium	Array, Hash Table, Binary Search +1
1583	Count Unhappy Friends	Medium	Array, Simulation
1599	Maximum Profit of Operating a Centennial Wheel	Medium	Array, Simulation
1680	Concatenation of Consecutive Binary Numbers	Medium	Bit Manipulation, Math, Simulation
1701	Average Waiting Time	Medium	Array, Simulation
1706	Where Will the Ball Fall	Medium	Array, Matrix, Simulation
1801	Number of Orders in the Backlog	Medium	Array, Simulation, Heap (Priority Queue)
1806	Minimum Number of Operations to Reinitialize a Permutation	Medium	Array, Math, Simulation
1823	Find the Winner of the Circular Game	Medium	Recursion, Queue, Array +2
1860	Incremental Memory Leak	Medium	Math, Simulation
1894	Find the Student that Will Replace the Chalk	Medium	Array, Binary Search, Prefix Sum +1
1910	Remove All Occurrences of a Substring	Medium	Stack, String, Simulation
1914	Cyclically Rotating a Grid	Medium	Array, Matrix, Simulation
2028	Find Missing Observations	Medium	Array, Math, Simulation
2043	Simple Bank System	Medium	Design, Array, Hash Table +1
2075	Decode the Slanted Ciphertext	Medium	String, Simulation
2079	Watering Plants	Medium	Array, Simulation
2105	Watering Plants II	Medium	Array, Two Pointers, Simulation
2109	Adding Spaces to a String	Medium	Array, Two Pointers, String +1
2120	Execution of All Suffix Instructions Staying in a Grid	Medium	String, Simulation
2149	Rearrange Array Elements by Sign	Medium	Array, Two Pointers, Simulation
2161	Partition Array According to Given Pivot	Medium	Array, Two Pointers, Simulation
2177	Find Three Consecutive Integers That Sum to a Given Number	Medium	Math, Simulation
2181	Merge Nodes in Between Zeros	Medium	Linked List, Simulation
2201	Count Artifacts That Can Be Extracted	Medium	Array, Hash Table, Simulation
2211	Count Collisions on a Road	Medium	Stack, String, Simulation
2221	Find Triangular Sum of an Array	Medium	Array, Math, Combinatorics +1
2257	Count Unguarded Cells in the Grid	Medium	Array, Matrix, Simulation
2295	Replace Elements in an Array	Medium	Array, Hash Table, Simulation
2326	Spiral Matrix IV	Medium	Array, Linked List, Matrix +1
2327	Number of People Aware of a Secret	Medium	Queue, Dynamic Programming, Simulation
2352	Equal Row and Column Pairs	Medium	Array, Hash Table, Matrix +1
2365	Task Scheduler II	Medium	Array, Hash Table, Simulation
2380	Time Needed to Rearrange a Binary String	Medium	String, Dynamic Programming, Simulation
2390	Removing Stars From a String	Medium	Stack, String, Simulation
2462	Total Cost to Hire K Workers	Medium	Array, Two Pointers, Simulation +1
2482	Difference Between Ones and Zeros in Row and Column	Medium	Array, Matrix, Simulation
2502	Design Memory Allocator	Medium	Design, Array, Hash Table +1
2507	Smallest Value After Replacing With Sum of Prime Factors	Medium	Math, Number Theory, Simulation
2593	Find Score of an Array After Marking All Elements	Medium	Array, Hash Table, Sorting +2
2596	Check Knight Tour Configuration	Medium	Depth-First Search, Breadth-First Search, Array +2
2679	Sum in a Matrix	Medium	Array, Matrix, Sorting +2
2766	Relocate Marbles	Medium	Array, Hash Table, Sorting +1
2961	Double Modular Exponentiation	Medium	Array, Math, Simulation
348	Design Tic-Tac-ToePremium	Medium	Design, Array, Hash Table +2
353	Design Snake GamePremium	Medium	Design, Queue, Array +2
544	Output Contest MatchesPremium	Medium	Recursion, String, Simulation
723	Candy CrushPremium	Medium	Array, Two Pointers, Matrix +1
755	Pour WaterPremium	Medium	Array, Simulation
1756	Design Most Recently Used QueuePremium	Medium	Design, Array, Linked List +3
2061	Number of Spaces Cleaning Robot CleanedPremium	Medium	Array, Matrix, Simulation
2069	Walking Robot Simulation II	Medium	Design, Simulation

Hard (10)

#	Problem	Difficulty	Topics
68	Text Justification	Hard	Array, String, Simulation
749	Contain Virus	Hard	Depth-First Search, Breadth-First Search, Array +2
1606	Find Servers That Handled Most Number of Requests	Hard	Array, Ordered Set, Simulation +1
2056	Number of Valid Move Combinations On Chessboard	Hard	Array, String, Backtracking +1
2296	Design a Text Editor	Hard	Stack, Design, Linked List +3
2402	Meeting Rooms III	Hard	Array, Hash Table, Sorting +2
2532	Time to Cross a Bridge	Hard	Array, Simulation, Heap (Priority Queue)
2751	Robot Collisions	Hard	Stack, Array, Sorting +1
158	Read N Characters Given read4 II - Call Multiple TimesPremium	Hard	Array, Interactive, Simulation
2534	Time Taken to Cross the DoorPremium	Hard	Queue, Array, Simulation

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