DSA for Frontend bank

Arrays & Hashing

DSA for Frontend / 238 questions

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001 Two Sum Easy
002 Contains Duplicate Easy
003 Product of Array Except Self Medium
004 Maximum Subarray Medium
005 Maximum Product Subarray Medium
006 Longest Consecutive Sequence Medium
007 Rotate Array Medium
008 Majority Element Easy
009 Find All Numbers Disappeared in an Array Easy
010 First Missing Positive Hard
011 Path Sum II Medium
012 Populating Next Right Pointers in Each Node Medium
013 Car Fleet Medium
014 Reverse Nodes in k-Group Hard
015 Last Stone Weight Easy
016 Hand of Straights Medium
017 Merge Triplets to Form Target Triplet Medium
018 Detect Squares Medium
019 First Bad Version Easy
020 Ransom Note Easy
021 Path Sum Easy
022 Remove Element Easy
023 Length of Last Word Easy
024 Text Justification Hard
025 Minimum Size Subarray Sum Medium
026 Word Pattern Easy
027 Contains Duplicate II Easy
028 Summary Ranges Easy
029 Populating Next Right Pointers in Each Node II Medium
030 Evaluate Division Medium
031 Minimum Genetic Mutation Medium
032 Maximum Sum Circular Subarray Medium
033 Largest Element in an Array Easy
034 Second Largest Element in an Array Easy
035 Check if Array is Sorted Easy
036 Left Rotate an Array by One Place Easy
037 Left Rotate an Array by D Places Medium
038 Union of Two Sorted Arrays Easy
039 Maximum Consecutive Ones Easy
040 Majority Element (>n/2 times) Easy
041 Maximum Subarray (Kadane's Algorithm) Medium
042 Rearrange Array Elements by Sign Medium
043 Leaders in an Array Easy
044 Count Subarrays with Given Sum Medium
045 Majority Element II (>n/3 times) Medium
046 Largest Subarray with 0 Sum Medium
047 Merge Two Sorted Arrays Without Extra Space Hard
048 Reverse Pairs Hard
049 Lower Bound / Upper Bound Easy
050 Floor and Ceil in Sorted Array Easy
051 First and Last Occurrence in Sorted Array Medium
052 Number of Occurrences Easy
053 Find Square Root of a Number Easy
054 Row with Maximum 1s Medium
055 Compare Version Numbers Medium
056 Delete a Given Node When Node is Given Easy
057 Detect the Starting Point of the Loop Medium
058 Find the Length of the Loop Medium
059 Subset Sum I Medium
060 Check if a Number is Odd Easy
061 Check if a Number is a Power of 2 Easy
062 Sort a K-Sorted Array Medium
063 Minimum Number of Platforms Required Medium
064 N Meetings in One Room Medium
065 Subset Sum Equal to Target Medium
066 Swap Two Numbers Without Temp Variable Easy
067 Check Prime Number Easy
068 Print All Divisors of a Number Easy
069 Print Fibonacci Series Easy
070 Reverse an Array Easy
071 Find Maximum and Minimum in an Array Easy
072 Move Negative Numbers to One Side Easy
073 Union and Intersection of Two Sorted Arrays Easy
074 Cyclically Rotate an Array by One Easy
075 Kadane's Algorithm - Maximum Subarray Sum Medium
076 Minimize the Maximum Difference Between Heights Medium
077 Minimum Jumps to Reach End of Array Medium
078 Find Duplicate in Array of N+1 Integers Medium
079 Find All Pairs with Given Sum Easy
080 Common Elements in Three Sorted Arrays Medium
081 Rearrange Alternating Positive and Negative Items Medium
082 Subarray with Sum Equal to Zero Medium
083 Elements Appearing More Than N/K Times Medium
084 Chocolate Distribution Problem Medium
085 Three-Way Partitioning of an Array Medium
086 Minimum Swaps to Bring Elements Less Than K Together Medium
087 Minimum Bracket Reversals to Balance an Expression Medium
088 Search in a Rotated Sorted Array Medium
089 Square Root of an Integer Easy
090 Find the Majority Element Easy
091 Searching in an Array Where Adjacent Differ by At Most K Medium
092 Find Four Elements That Sum to a Given Value Medium
093 Maximum Sum with No Two Adjacent Elements Medium
094 Print All Subarrays with Sum Zero Medium
095 Find Starting Point of the Loop Medium
096 Evaluation of Postfix Expression Medium
097 Largest Rectangular Area in Histogram Hard
098 First Negative Integer in Every Window of Size K Medium
099 Maximum Sum of Non-Adjacent Nodes Hard
100 Buy Maximum Stocks with Daily Limit Medium
101 Minimize Cash Flow Among Friends Hard
102 M-Coloring Problem Medium
103 Subset Sum Problem Medium
104 The Knight's Tour Problem Hard
105 Connect N Ropes with Minimum Cost Medium
106 Minimum Cost Path Problem Medium
107 Partition Problem Medium
108 Optimal Strategy for a Game Hard
109 Word Wrap Problem Hard
110 Find the Two Non-Repeating Elements Medium
111 Subarray Sum Equals K Medium
112 Reverse the array Easy
113 Find the maximum and minimum element in an array Easy
114 Find the Kth max and min element of an array Medium
115 Given an array of 0s, 1s and 2s, sort it without using any sorting algorithm Medium
116 Move all the negative elements to one side of the array Easy
117 Find the Union and Intersection of two sorted arrays Easy
118 Write a program to cyclically rotate an array by one Easy
119 Find largest sum contiguous subarray Medium
120 Minimise the maximum difference between heights Medium
121 Minimum number of jumps to reach end of an array Medium
122 Find duplicate in an array of N+1 integers Medium
123 Merge two sorted arrays without using extra space Hard
124 Kadane's Algorithm Medium
125 Find all pairs of integers in array whose sum equals a given number Easy
126 Find common elements in 3 sorted arrays Medium
127 Rearrange the array alternately in positive and negative with O(1) extra space Medium
128 Find if there is any subarray with sum equal to 0 Medium
129 Find maximum product subarray Medium
130 Given an array of size n and a number k, find all elements appearing more than n/k times Medium
131 Maximum profit by buying and selling a share at most twice Hard
132 Find whether an array is a subset of another array Easy
133 Find the triplet that sums to a given value Medium
134 Three-way partitioning of an array around a given value Medium
135 Minimum swaps required to bring elements less equal K together Medium
136 Find the row with maximum number of 1s Medium
137 Convert a sentence into its equivalent mobile numeric keypad sequence Easy
138 Minimum number of bracket reversals needed to balance an expression Medium
139 Search a word in a 2D grid of characters Medium
140 Boyer-Moore algorithm for pattern searching Hard
141 Minimum number of swaps for bracket balancing Medium
142 Recursively remove all adjacent duplicates Medium
143 Find number of customers who could not get a computer Medium
144 Recursively print all sentences that can be formed from a list of word lists Hard
145 Find a fixed point (value equal to index) in a given array Easy
146 Maximum and minimum of an array using minimum number of comparisons Easy
147 Optimum location of point to minimize total distance Hard
148 Searching in an array where adjacent elements differ by at most k Medium
149 Maximum sum such that no two elements are adjacent Medium
150 Count triplets with sum smaller than a given value Medium
151 Merge two sorted arrays Easy
152 Print all subarrays with sum equal to zero Medium
153 Product array puzzle Medium
154 Minimum number of swaps required to sort the array Medium
155 Bishu and Soldiers Medium
156 Rasta and Kheshtak Medium
157 Kth smallest number Medium
158 Find the pivot element in a sorted array Easy
159 ROTI - Prata SPOJ Hard
160 DoubleHelix SPOJ Hard
161 Subset Sums Medium
162 Find the starting point of the loop Medium
163 Delete nodes which have a greater value on the right side Medium
164 Find the first non-repeating character from a stream of characters Medium
165 Replace every element with the least greater element on its right Hard
166 Given n appointments, find the conflicting appointments Medium
167 Water Connection Problem Medium
168 Maximum trains for which stoppage can be provided Hard
169 Buy maximum stocks if i stocks can be bought on the i-th day Medium
170 Find the minimum and maximum amount to buy all N candies Medium
171 Minimize cash flow among a given set of friends who have borrowed money from each other Hard
172 Minimum cost to cut a board into squares Medium
173 Find maximum meetings in one room Medium
174 Maximum product subset of an array Medium
175 Maximize array sum after K negations Easy
176 Maximize the sum of arr[i] * i Medium
177 Maximum sum of absolute difference of an array Medium
178 Maximize sum of consecutive differences in a circular array Medium
179 Minimum sum of absolute difference of pairs of two arrays Medium
180 DEFKIN - Defense of a Kingdom Hard
181 DIEHARD - Die Hard Hard
182 GERGOVIA - Wine trading in Gergovia Hard
183 Picking Up Chicks Medium
184 CHOCOLA - Chocolate Hard
185 ARRANGE - Arranging Amplifiers Hard
186 Find smallest number with given number of digits and sum of digits Medium
187 Tug of War Hard
188 Find the shortest safe route in a path with landmines Hard
189 Find the maximum number possible by doing at most K swaps Hard
190 Find if there is a path of more than k length from a source Hard
191 Arithmetic expression evaluation Hard
192 Largest rectangular area in a histogram Hard
193 Check whether an expression contains a redundant bracket Medium
194 Find the first circular tour that visits all petrol pumps Medium
195 Sum of minimum and maximum elements of all subarrays of size K Hard
196 Minimum sum of squares of character counts after removing K characters Hard
197 Maximum of all subarrays of size K Hard
198 Kth smallest and largest element in an unsorted array Medium
199 Smallest range covering elements from K lists Hard
200 Minimum sum of two numbers formed from the digits of an array Medium
201 Search in a maze Hard
202 Minimum steps by a Knight Medium
203 Making wired connections Medium
204 Find whether it is possible to finish all tasks from given dependencies Medium
205 Given a sorted dictionary of an alien language, find the order of characters Hard
206 Travelling Salesman Problem Hard
207 Oliver and the Game Hard
208 M-Colouring Problem Medium
209 Minimum edges to reverse to make a path from source to destination Hard
210 Paths to travel each node using each edge (Seven Bridges) Hard
211 Vertex Cover Problem Hard
212 Chinese Postman / Route Inspection Problem Hard
213 Minimize the cashflow among friends who have borrowed money from each other Hard
214 Two Clique Problem Hard
215 Find the shortest unique prefix for every word in a given list Hard
216 Binomial Coefficient Problem Medium
217 Friends Pairing Problem Medium
218 Gold Mine Problem Medium
219 Painting the Fence Problem Medium
220 Maximize the Cut Segments Medium
221 Space Optimized Solution of LCS Medium
222 Maximum Length Chain of Pairs Medium
223 Maximum sum of pairs with a specific difference Medium
224 Min Cost Path Problem Medium
225 Minimum number of jumps to reach the end Medium
226 Minimum cost to fill a given weight in a bag Hard
227 Minimum removals from array to make max-min <= K Hard
228 Count the number of ways to reach a given score in a game Medium
229 Largest sum contiguous subarray Medium
230 Smallest sum contiguous subarray Medium
231 Largest Independent Set Problem Hard
232 Coin game winner where every player has three choices Medium
233 Maximum profit from buying/selling a share at most twice Hard
234 Mobile Numeric Keypad Problem Medium
235 Maximum profit from buying/selling a share at most K times Hard
236 Find the two non-repeating elements in an array of repeating elements Medium
237 Power Set Medium
238 Longest Repeating Char Replacement Medium