Best Time to Buy and Sell Stock II

best-time-to-buy-and-sell-stock-ii

Binary Tree Maximum Path Sum

binary-tree-maximum-path-sum

Delete and Earn

delete-and-earn

Subarray Sums Divisible by K

subarray-sums-divisible-by-k

Minimum Knight Moves

minimum-knight-moves

Count Ways To Build Good Strings

count-ways-to-build-good-strings

Number of Good Binary Strings

number-of-good-binary-strings

Integer to Roman

integer-to-roman

Permutations

permutations

Best Time to Buy and Sell Stock

best-time-to-buy-and-sell-stock

Best Time to Buy and Sell Stock III

best-time-to-buy-and-sell-stock-iii

Evaluate Reverse Polish Notation

evaluate-reverse-polish-notation

Minimum Size Subarray Sum

minimum-size-subarray-sum

Sliding Window Maximum

sliding-window-maximum

Range Addition

range-addition

Insert Delete GetRandom O(1)

insert-delete-getrandom-o1

The Maze

the-maze

Subarray Sum Equals K

subarray-sum-equals-k

Design In-Memory File System

design-in-memory-file-system

Asteroid Collision

asteroid-collision

Transpose Matrix

transpose-matrix

Smallest Range II

smallest-range-ii

Minimum Costs Using the Train Line

minimum-costs-using-the-train-line

Two Sum

two-sum

Trapping Rain Water

trapping-rain-water

Merge Intervals

merge-intervals

Insert Interval

insert-interval

Word Ladder

word-ladder

LRU Cache

lru-cache

Best Time to Buy and Sell Stock IV

best-time-to-buy-and-sell-stock-iv

Course Schedule

course-schedule

3Sum Smaller

3sum-smaller

Find Median from Data Stream

find-median-from-data-stream

Reconstruct Itinerary

reconstruct-itinerary

Coin Change II

coin-change-ii

Knight Probability in Chessboard

knight-probability-in-chessboard

Consecutive Numbers Sum

consecutive-numbers-sum

Time Based Key-Value Store

time-based-key-value-store

Pairs of Songs With Total Durations Divisible by 60

pairs-of-songs-with-total-durations-divisible-by-60

Process Tasks Using Servers

process-tasks-using-servers

Maximum Length of Repeated Subarray

maximum-length-of-repeated-subarray

Best Position for a Service Centre

best-position-for-a-service-centre

First Completely Painted Row or Column

first-completely-painted-row-or-column

Citadel

#	Title	Difficulty	Frequency
122	Best Time to Buy and Sell Stock II	Medium	1.36
124	Binary Tree Maximum Path Sum	Hard	34.32
740	Delete and Earn	Medium	104.44
974	Subarray Sums Divisible by K	Medium	45.46
1197	Minimum Knight Moves	Medium	35.77
2466	Count Ways To Build Good Strings	Medium	50.79
2533	Number of Good Binary Strings	Medium	158.09