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CIP Part 2 C#
1.
Two Pointers
K-diff Pairs in an Array
Solution: K-diff Pairs in an Array
Longest Mountain in Array
Solution: Longest Mountain in Array
Meeting Scheduler
Solution: Meeting Scheduler
Maximize Greatness of an Array
Solution: Maximize Greatness of an Array
Find the Original Typed String I
Solution: Find the Original Typed String I
Remove Duplicates from Sorted List II
Solution: Remove Duplicates from Sorted List II
Count the Number of Fair Pairs
Solution: Count the Number of Fair Pairs
Sum of Square Numbers
Solution: Sum of Square Numbers
Find Beautiful Indices in the Given Array II
Solution: Find Beautiful Indices in the Given Array II
Number of Subsequences That Satisfy the Given Sum Condition
Solution: Number of Subsequences That Satisfy the Given Sum Condi
Zigzag Iterator
Solution: Zigzag Iterator
Length of Last Word
Solution: Length of Last Word
2.
Fast and Slow Pointers
3.
Sliding Window
Longest Substring with At Most K Distinct Characters
Solution: Longest Substring with At Most K Distinct Characters
Maximum Points You Can Obtain from Cards
Solution: Maximum Points You Can Obtain from Cards
Minimum Swaps to Group All 1's Together II
Solution: Minimum Swaps to Group All 1's Together II
Maximum Number of Occurrences of a Substring
Solution: Maximum Number of Occurrences of a Substring
Count Number of Nice Subarrays
Solution: Count Number of Nice Subarrays
Maximum Erasure Value
Solution: Maximum Erasure Value
Maximum Sum of Distinct Subarrays With Length K
Solution: Maximum Sum of Distinct Subarrays With Length K
Longest Nice Subarray
Solution: Longest Nice Subarray
Count Vowel Substrings of a String
Solution: Count Vowel Substrings of a String
Reschedule Meetings for Maximum Free Time I
Solution: Reschedule Meetings for Maximum Free Time I
Grumpy Bookstore Owner
Solution: Grumpy Bookstore Owner
Longest Strictly Increasing or Strictly Decreasing Subarray
Solution: Longest Strictly Increasing or Strictly Decreasing Suba
4.
Intervals
5.
In-Place Manipulation of a Linked List
6.
Heaps
Sort Characters By Frequency
Solution: Sort Characters By Frequency
Furthest Building You Can Reach
Solution: Furthest Building You Can Reach
Trapping Rain Water II
Solution: Trapping Rain Water II
Maximum Number of Events That Can Be Attended
Solution: Maximum Number of Events That Can Be Attended
Single-Threaded CPU
Solution: Single-Threaded CPU
Hand of Straights
Solution: Hand of Straights
Last Stone Weight
Solution: Last Stone Weight
7.
K-way merge
8.
Top K Elements
9.
Modified Binary Search
Search a 2D Matrix
Solution: Search a 2D Matrix
Find the Smallest Divisor Given a Threshold
Solution: Find the Smallest Divisor Given a Threshold
Zero Array Transformation II
Solution: Zero Array Transformation II
House Robber IV
Solution: House Robber IV
Minimum Number of Days to Make m Bouquets
Solution: Minimum Number of Days to Make m Bouquets
Valid Perfect Square
Solution: Valid Perfect Square
Peak Index in a Mountain Array
Solution: Peak Index in a Mountain Array
10.
Subsets
11.
Greedy Techniques
Minimum Adjacent Swaps to Make a Valid Array
Solution: Minimum Adjacent Swaps to Make a Valid Array
Special Binary String
Solution: Special Binary String
Maximize Distance to Closest Person
Solution: Maximize Distance to Closest Person
Minimum Number of Taps to Open to Water a Garden
Solution: Minimum Number of Taps to Open to Water a Garden
Valid Parenthesis String
Solution: Valid Parenthesis String
Minimum Number of Swaps to Make the String Balanced
Solution: Minimum Number of Swaps to Make the String Balanced
Minimum Number of Arrows to Burst Balloons
Solution: Minimum Number of Arrows to Burst Balloons
Minimum Increment to Make Array Unique
Solution: Minimum Increment to Make Array Unique
Zero Array Transformation III
Solution: Zero Array Transformation III
12.
Backtracking
Combination Sum II
Solution: Combination Sum II
13.
Dynamic Programming
Minimum Cost For Tickets
Solution: Minimum Cost For Tickets
Count Palindromic Subsequences
Solution: Count Palindromic Subsequences
Unique Paths II
Solution: Unique Paths II
Best Time to Buy and Sell Stock IV
Solution: Best Time to Buy and Sell Stock IV
Delete and Earn
Solution: Delete and Earn
Longest String Chain
Solution: Longest String Chain
Last Stone Weight II
Solution: Last Stone Weight II
Stickers to Spell Word
Solution: Stickers to Spell Word
New 21 Game
Solution: New 21 Game
Odd Even Jump
Solution: Odd Even Jump
2 Keys Keyboard
Solution: 2 Keys Keyboard
Minimum Cost to Cut a Stick
Solution: Minimum Cost to Cut a Stick
Domino and Tromino Tiling
Solution: Domino and Tromino Tiling
Maximum Number of Events That Can Be Attended II
Solution: Maximum Number of Events That Can Be Attended II
Scramble String
Solution: Scramble String
Minimum Falling Path Sum
Solution: Minimum Falling Path Sum
Find the Minimum Amount of Time to Brew Potions
Solution: Find the Minimum Amount of Time to Brew Potions
Target Sum
Solution: Target Sum
Maximum Sum Circular Subarray
Solution: Maximum Sum Circular Subarray
Coin Change II
Solution: Coin Change II
Maximum Sum of 3 Non-Overlapping Subarrays
Solution: Maximum Sum of 3 Non-Overlapping Subarrays
Ugly Number II
Solution: Ugly Number II
Longest Palindromic Subsequence
Solution: Longest Palindromic Subsequence
Different Ways to Add Parentheses
Solution: Different Ways to Add Parentheses
Best Time to Buy and Sell Stock with Transaction Fee
Solution: Best Time to Buy and Sell Stock with Transaction Fee
Minimum Operations to Reduce an Integer to 0
Solution: Minimum Operations to Reduce an Integer to 0
14.
Cyclic Sort
15.
Topological Sort
16.
Sort and Search
Minimum Absolute Difference
Solution: Minimum Absolute Difference
Most Profit Assigning Work
Solution: Most Profit Assigning Work
Rank Transform of an Array
Solution: Rank Transform of an Array
Relative Sort Array
Solution: Relative Sort Array
17.
Matrices
Search a 2D Matrix II
Solution: Search a 2D Matrix II
18.
Stacks
Next Greater Element II
Solution: Next Greater Element II
Sum of Subarray Minimums
Solution: Sum of Subarray Minimums
Car Fleet
Solution: Car Fleet
Clear Digits
Solution: Clear Digits
Remove All Occurrences of a Substring
Solution: Remove All Occurrences of a Substring
Subarray With Elements Greater Than Varying Threshold
Solution: Subarray With Elements Greater Than Varying Threshold
132 Pattern
Solution: 132 Pattern
Sum of Subarray Ranges
Solution: Sum of Subarray Ranges
Add Two Numbers II
Solution: Add Two Numbers II
Reverse Substrings Between Each Pair of Parentheses
Solution: Reverse Substrings Between Each Pair of Parentheses
Maximum Nesting Depth of the Parentheses
Solution: Maximum Nesting Depth of the Parentheses
Final Prices With a Special Discount in a Shop
Solution: Final Prices With a Special Discount in a Shop
Minimum Add to Make Parentheses Valid
Solution: Minimum Add to Make Parentheses Valid
19.
Graphs
Walls and Gates
Solution: Walls and Gates
Snakes and Ladders
Solution: Snakes and Ladders
The Maze
Solution: The Maze
Shortest Path in Binary Matrix
Solution: Shortest Path in Binary Matrix
All Nodes Distance K in Binary Tree
Solution: All Nodes Distance K in Binary Tree
Making A Large Island
Solution: Making A Large Island
Minimum Edge Reversals So Every Node Is Reachable
Solution: Minimum Edge Reversals So Every Node Is Reachable
Minimum Knight Moves
Solution: Minimum Knight Moves
Keys and Rooms
Solution: Keys and Rooms
Is Graph Bipartite?
Solution: Is Graph Bipartite?
Possible Bipartition
Solution: Possible Bipartition
Divide Nodes Into the Maximum Number of Groups
Solution: Divide Nodes Into the Maximum Number of Groups
Min Cost to Connect All Points
Solution: Min Cost to Connect All Points
20.
Tree Depth-First Search
Path Sum III
Solution: Path Sum III
Boundary of Binary Tree
Solution: Boundary of Binary Tree
Convert Sorted List to Binary Search Tree
Solution: Convert Sorted List to Binary Search Tree
Sum Root to Leaf Numbers
Solution: Sum Root to Leaf Numbers
Count Complete Tree Nodes
Solution: Count Complete Tree Nodes
Nested List Weight Sum
Solution: Nested List Weight Sum
Binary Tree Postorder Traversal
Solution: Binary Tree Postorder Traversal
21.
Tree Breadth-First Search
Binary Tree Vertical Order Traversal
Solution: Binary Tree Vertical Order Traversal
Maximum Width of Binary Tree
Solution: Maximum Width of Binary Tree
Cousins in Binary Tree
Solution: Cousins in Binary Tree
Cousins in Binary Tree
Solution: Cousins in Binary Tree
Minimum Depth of Binary Tree
Solution: Minimum Depth of Binary Tree
Populating Next Right Pointers in Each Node II
Solution: Populating Next Right Pointers in Each Node II
Find Largest Value in Each Tree Row
Solution: Find Largest Value in Each Tree Row
22.
Trie
23.
Hash Maps
Make Array Zero by Subtracting Equal Amounts
Solution: Make Array Zero by Subtracting Equal Amounts
Find Common Characters
Solution: Find Common Characters
Count Servers that Communicate
Solution: Count Servers that Communicate
Check If N and Its Double Exist
Solution: Check If N and Its Double Exist
Check If Array Pairs Are Divisible by k
Solution: Check If Array Pairs Are Divisible by k
Rabbits in Forest
Solution: Rabbits in Forest
Max Sum of a Pair With Equal Sum of Digits
Solution: Max Sum of a Pair With Equal Sum of Digits
Longest Harmonious Subsequence
Solution: Longest Harmonious Subsequence
Finding 3-Digit Even Numbers
Solution: Finding 3-Digit Even Numbers
Subarray Sums Divisible by K
Solution: Subarray Sums Divisible by K
Number of Black Blocks
Solution: Number of Black Blocks
Minimum Number of Steps to Make Two Strings Anagram
Solution: Minimum Number of Steps to Make Two Strings Anagram
Degree of an Array
Solution: Degree of an Array
Make Sum Divisible by P
Solution: Make Sum Divisible by P
Find the Prefix Common Array of Two Arrays
Solution: Find the Prefix Common Array of Two Arrays
Find Missing and Repeated Values
Solution: Find Missing and Repeated Values
Number of Divisible Triplet Sums
Solution: Number of Divisible Triplet Sums
Number of Matching Subsequences
Solution: Number of Matching Subsequences
24.
Knowing What to Track
Minimum Operations to Write the Letter Y on a Grid
Solution: Minimum Operations to Write the Letter Y on a Grid
Unique Length-3 Palindromic Subsequences
Solution: Unique Length-3 Palindromic Subsequences
Shortest Palindrome
Solution: Shortest Palindrome
Find the Celebrity
Solution: Find the Celebrity
Kids With the Greatest Number of Candies
Solution: Kids With the Greatest Number of Candies
Fruits Into Baskets II
Solution: Fruits Into Baskets II
Number of Good Pairs
Solution: Number of Good Pairs
Maximum Product of Three Numbers
Solution: Maximum Product of Three Numbers
Remove Outermost Parentheses
Solution: Remove Outermost Parentheses
Max Chunks To Make Sorted
Solution: Max Chunks To Make Sorted
Count Vowel Strings in Ranges
Solution: Count Vowel Strings in Ranges
Shortest Subarray with Sum at Least K
Solution: Shortest Subarray with Sum at Least K
Word Subsets
Solution: Word Subsets
Find the Highest Altitude
Solution: Find the Highest Altitude
Summary Ranges
Solution: Summary Ranges
Special Array I
Solution: Special Array I
Number of Ways to Split Array
Solution: Number of Ways to Split Array
String Compression III
Solution: String Compression III
Find Longest Special Substring That Occurs Thrice I
Solution: Find Longest Special Substring That Occurs Thrice I
Guess the Word
Solution: Guess the Word
Best Sightseeing Pair
Solution: Best Sightseeing Pair
Shortest Unsorted Continuous Subarray
Solution: Shortest Unsorted Continuous Subarray
Bitwise ORs of Subarrays
Solution: Bitwise ORs of Subarrays
Check if Array Is Sorted and Rotated
Solution: Check if Array Is Sorted and Rotated
Valid Word
Solution: Valid Word
Running Sum of 1d Array
Solution: Running Sum of 1d Array
Find Numbers with Even Number of Digits
Solution: Find Numbers with Even Number of Digits
Maximum Difference Between Increasing Elements
Solution: Maximum Difference Between Increasing Elements
25.
Union Find
Power Grid Maintenance
Solution: Power Grid Maintenance
Number of Operations to Make Network Connected
Solution: Number of Operations to Make Network Connected
26.
Custom Data Structures
27.
Bitwise Manipulation
Single Number III
Solution: Single Number III
Power of Four
Solution: Power of Four
28.
Math and Geometry
The kth Factor of n
Solution: The kth Factor of n
Find the Winner of the Circular Game
Solution: Find the Winner of the Circular Game
Build Array from Permutation
Solution: Build Array from Permutation
Minimum Moves to Equal Array Elements
Solution: Minimum Moves to Equal Array Elements
Angle Between Hands of a Clock
Solution: Angle Between Hands of a Clock
Type of Triangle
Solution: Type of Triangle
Convert Binary Number in a Linked List to Integer
Solution: Convert Binary Number in a Linked List to Integer
Count the Hidden Sequences
Solution: Count the Hidden Sequences
Find N Unique Integers Sum up to Zero
Solution: Find N Unique Integers Sum up to Zero
Excel Sheet Column Number
Solution: Excel Sheet Column Number
Water Bottles
Solution: Water Bottles
Excel Sheet Column Title
Solution: Excel Sheet Column Title
Ugly Number
Solution: Ugly Number
Reach a Number
Solution: Reach a Number
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CIP Part 2 C#
Keys and Rooms
Try to solve the Keys and Rooms problem.
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Statement
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Statement
You are given
n
rooms labeled from
...