# Problem Code Type Topic Companies Average Time Score
1 Allocate Books code Binary Search
56:58 350
2 Implement Power Function code Binary Search
57:12 275
3 Matrix Median code Binary Search
62:15 225
4 Matrix Search code Binary Search
34:50 250
5 Median of Array code Binary Search 71:43 325
6 Painter's Partition Problem code Binary Search
66:20 350
7 Rotated Sorted Array Search code Binary Search
53:28 325
8 Search for a Range code Binary Search
39:29 250
9 Sorted Insert Position code Binary Search
23:30 250
10 Square Root of Integer code Binary Search 39:48 275
11 Distinct Numbers in Window code Heaps And Maps 35:04 600
12 LRU Cache code Heaps And Maps 61:57 1000
13 Magician and Chocolates code Heaps And Maps
36:49 250
14 Merge K Sorted Lists code Heaps And Maps 38:44 600
15 N max pair combinations code Heaps And Maps 74:18 200
16 Ways to form Max Heap code Heaps And Maps 73:58 200
17 Design Messenger subjective System Design Interview Questions 41:40 600
18 Design Search Typeahead subjective System Design Interview Questions
53:20 400
19 Design Twitter subjective System Design Interview Questions 38:20 600
20 Design URL Shortener subjective System Design Interview Questions 45:00 300
21 2-Sum Binary Tree code Tree Data Structure 54:01 400
22 Balanced Binary Tree code Tree Data Structure 27:51 275
23 Binary Tree From Inorder And Postorder code Tree Data Structure 40:25 375
24 BST Iterator code Tree Data Structure 34:51 500
25 Construct Binary Tree From Inorder And Preorder code Tree Data Structure 39:32 375
26 Flatten Binary Tree to Linked List code Tree Data Structure 38:25 500
27 Hotel Reviews code Tree Data Structure 65:27 200
28 Identical Binary Trees code Tree Data Structure 10:48 300
29 Inorder Traversal code Tree Data Structure 30:09 350
30 Inorder Traversal of Cartesian Tree code Tree Data Structure 42:27 300
31 Invert the Binary Tree code Tree Data Structure
11:50 300
32 Kth Smallest Element In Tree code Tree Data Structure 26:30 300
33 Least Common Ancestor code Tree Data Structure 52:07 450
34 Max Depth of Binary Tree code Tree Data Structure 6:18 350
35 Min Depth of Binary Tree code Tree Data Structure 16:04 350
36 Order of People Heights code Tree Data Structure
64:19 700
37 Path Sum code Tree Data Structure 24:44 350
38 Populate Next Right Pointers Tree code Tree Data Structure 43:36 900
39 Postorder Traversal code Tree Data Structure 27:38 350
40 Preorder Traversal code Tree Data Structure 13:51 350
41 Recover Binary Search Tree code Tree Data Structure
50:22 750
42 Root to Leaf Paths With Sum code Tree Data Structure 36:11 350
43 Shortest Unique Prefix code Tree Data Structure
61:13 350
44 Sorted Array To Balanced BST code Tree Data Structure 25:43 300
45 Sum Root to Leaf Numbers code Tree Data Structure
40:09 350
46 Symmetric Binary Tree code Tree Data Structure 19:57 300
47 Vertical Order traversal of Binary Tree code Tree Data Structure 62:14 200
48 ZigZag Level Order Traversal BT code Tree Data Structure 38:11 350
49 Assign Mice to Holes code Greedy Algorithm 19:05 300
50 Bulbs code Greedy Algorithm
19:52 200
51 Distribute Candy code Greedy Algorithm 53:22 300
52 Gas Station code Greedy Algorithm 48:05 700
53 Highest Product code Greedy Algorithm 26:15 200
54 Majority Element code Greedy Algorithm
16:53 400
55 Seats code Greedy Algorithm 62:31 300
56 Evaluate Expression code Stacks And Queues
31:01 400
57 Largest Rectangle in Histogram code Stacks And Queues
56:35 450
58 Min Stack code Stacks And Queues 40:31 400
59 Nearest Smaller Element code Stacks And Queues 39:22 350
60 Rain Water Trapped code Stacks And Queues 51:59 400
61 Redundant Braces code Stacks And Queues 39:57 300
62 Simplify Directory Path code Stacks And Queues
48:37 250
63 Sliding Window Maximum code Stacks And Queues 59:31 450
64 Actors and their Movies sql SQL Programming
23:38 100
65 Movie Character sql SQL Programming
22:05 100
66 Neutral Reviewers sql SQL Programming
17:40 100
67 Short Films sql SQL Programming
20:15 100
68 100 People in a Circle objective Puzzles
10:56 40
69 Ants on a Triangle objective Puzzles
4:37 40
70 Arrange Cubes objective Puzzles
14:42 40
71 Bee Travel objective Puzzles
7:33 40
72 Blindfolded Coin Toss objective Puzzles
3:05 40
73 Breaking Chocolate Bars objective Puzzles
4:59 40
74 Cats and a Square objective Puzzles
7:02 40
75 Celebrity Problem objective Puzzles
7:56 40
76 Color of the Bear objective Puzzles
3:26 40
77 Color of the last ball objective Puzzles
4:49 40
78 Color of the last ball II objective Puzzles
3:06 40
79 Cross the Bridge objective Puzzles
8:17 40
80 Cross the Bridge II objective Puzzles
5:11 40
81 Daughters' Ages objective Puzzles
11:54 40
82 Dinner Hand Shakes objective Puzzles
6:36 40
83 Divide Gold Bar objective Puzzles 5:37 40
84 Divide the Cake objective Puzzles
2:56 40
85 Eggs and Building objective Puzzles 12:06 40
86 Equilateral Triangles using Toothpicks objective Puzzles
5:38 40
87 Fake Note objective Puzzles
5:03 40
88 Fastest Horses objective Puzzles
6:38 40
89 Find the Defective Ball objective Puzzles
5:56 40
90 Find the Defective Ball II objective Puzzles
2:49 40
91 Gates of Heaven objective Puzzles
7:25 40
92 Genie and Hats objective Puzzles
6:58 40
93 Good Processor objective Puzzles
7:23 40
94 Helium Balloon objective Puzzles
1:52 40
95 Jelly Beans Jars objective Puzzles
6:58 40
96 Last Palindromic Date objective Puzzles
10:15 40
97 Light Switches in the Cellar objective Puzzles 2:51 40
98 Make a Statement objective Puzzles 4:07 40
99 Marbles in Jar objective Puzzles
10:05 40
100 Measure Milk by Cans objective Puzzles 13:36 40
101 Measure Time by Burning Ropes objective Puzzles
6:13 40
102 Measure Time by Hourglass objective Puzzles
8:22 40
103 Medicine Chest on a Boat objective Puzzles
8:21 40
104 Min Elevator Trips objective Puzzles
18:29 40
105 Monkeys and Doors objective Puzzles 10:17 40
106 Next Number objective Puzzles
16:37 40
107 Next Number II objective Puzzles 2:59 40
108 One Mile on the Globe objective Puzzles
7:15 40
109 Prisoners and Poison objective Puzzles 15:44 40
110 Quarters on a Table objective Puzzles
4:34 40
111 Ratio of Boys and Girls objective Puzzles
13:38 40
112 Six Colored Cubes objective Puzzles
12:07 40
113 Spider's Web objective Puzzles 3:32 40
114 Spinning Disc's Direction objective Puzzles
6:16 40
115 Ten Black and White Socks objective Puzzles
4:01 40
116 The Tribe objective Puzzles 5:49 40
117 Train Station objective Puzzles
17:04 40
118 Two Numbers objective Puzzles
11:14 40
119 Two Pills each day objective Puzzles
3:19 40
120 Wizards and Drawves objective Puzzles
12:12 40
121 World Trips objective Puzzles
8:48 40
122 Convert Integer To Roman Number shell Regex and Functions
23:20 400
123 Sort by Frequency shell Regex and Functions
47:57 250
124 Swap Forward And Backward Slash shell Regex and Functions
15:14 200
125 Valid Email Address shell Regex and Functions
26:25 350
126 Lines in a given range shell Basic Shell Commands
30:55 200
127 Remove Punctuations shell Basic Shell Commands
16:36 250
128 Transform CSV shell Basic Shell Commands
21:56 300
129 Valid phone number shell Basic Shell Commands
21:21 150
130 Combination Sum code Backtracking 53:09 300
131 Combination Sum II code Backtracking 35:34 300
132 Combinations code Backtracking 39:31 300
133 Generate all Parentheses II code Backtracking
45:17 350
134 Gray Code code Backtracking
50:24 350
135 Kth Permutation Sequence code Backtracking 69:31 350
136 Letter Phone code Backtracking 47:22 250
137 NQueens code Backtracking 63:46 550
138 Palindrome Partitioning code Backtracking 58:20 300
139 Permutations code Backtracking 35:04 350
140 Subset code Backtracking 54:49 250
141 Subsets II code Backtracking 34:13 300
142 Sudoku code Backtracking 56:02 700
143 Different Bits Sum Pairwise code Bit Manipulation
44:27 300
144 Divide Integers code Bit Manipulation 55:53 250
145 Min XOR value code Bit Manipulation 35:35 200
146 Number of 1 Bits code Bit Manipulation 8:29 200
147 Reverse Bits code Bit Manipulation 22:16 225
148 Single Number code Bit Manipulation 11:26 275
149 Single Number II code Bit Manipulation 36:11 275
150 Arrange II code Dynamic Programming 70:52 350
151 Best Time to Buy and Sell Stocks I code Dynamic Programming 24:48 300
152 Best Time to Buy and Sell Stocks II code Dynamic Programming 34:20 225
153 Best Time to Buy and Sell Stocks III code Dynamic Programming 46:51 700
154 Coin Sum Infinite code Dynamic Programming
54:06 225
155 Coins in a Line code Dynamic Programming
51:14 300
156 Count Permutations of BST code Dynamic Programming
80:15 400
157 Distinct Subsequences code Dynamic Programming
49:56 325
158 Dungeon Princess code Dynamic Programming
57:14 300
159 Edit Distance code Dynamic Programming
40:08 300
160 Equal Average Partition code Dynamic Programming 85:01 350
161 Evaluate Expression To True code Dynamic Programming 66:29 350
162 Flip Array code Dynamic Programming
82:44 200
163 Interleaving Strings code Dynamic Programming
46:55 500
164 Intersecting Chords in a Circle code Dynamic Programming
57:38 300
165 Jump Game Array code Dynamic Programming 35:28 225
166 Kth Manhattan Distance Neighbourhood code Dynamic Programming 64:51 200
167 Largest area of rectangle with permutations code Dynamic Programming
62:41 200
168 Length of Longest Subsequence code Dynamic Programming
56:24 200
169 Longest Arithmetic Progression code Dynamic Programming
61:24 200
170 Longest Increasing Subsequence code Dynamic Programming 27:14 300
171 Longest valid Parentheses code Dynamic Programming
45:15 700
172 Max Product Subarray code Dynamic Programming 55:17 300
173 Max Rectangle in Binary Matrix code Dynamic Programming
62:43 350
174 Max Sum Path in Binary Tree code Dynamic Programming 46:13 400
175 Max Sum Without Adjacent Elements code Dynamic Programming 50:16 225
176 Min Jumps Array code Dynamic Programming 58:05 300
177 Min Sum Path in Matrix code Dynamic Programming 27:16 300
178 Min Sum Path in Triangle code Dynamic Programming
37:07 300
179 N digit numbers with digit sum S code Dynamic Programming
58:01 200
180 Palindrome Partitioning II code Dynamic Programming 46:01 400
181 Queen Attack code Dynamic Programming
75:51 350
182 Regular Expression II code Dynamic Programming
58:40 500
183 Regular Expression Match code Dynamic Programming
62:52 500
184 Repeating Sub-Sequence code Dynamic Programming
52:30 300
185 Rod Cutting code Dynamic Programming
77:18 350
186 Scramble String code Dynamic Programming
57:05 500
187 Shortest common superstring code Dynamic Programming
74:03 200
188 Stairs code Dynamic Programming 13:53 225
189 Sub Matrices with sum Zero code Dynamic Programming
74:42 200
190 Tushar's Birthday Bombs code Dynamic Programming
80:41 200
191 Tushar's Birthday Party code Dynamic Programming 60:51 200
192 Unique Binary Search Trees II code Dynamic Programming 29:23 400
193 Unique Paths in a Grid code Dynamic Programming
28:36 300
194 Ways to color a 3xN Board code Dynamic Programming 62:17 200
195 Ways to Decode code Dynamic Programming 61:14 225
196 Word Break code Dynamic Programming
IBM
50:54 400
197 Word Break II code Dynamic Programming
IBM
55:05 350
198 Another chocolate game code Codersbit
36:38 200
199 Array and Prime Divisors code Codersbit
27:04 150
200 Delete and Conquer code Codersbit
9:59 150
201 Distinct Primes code Codersbit
60:36 150
202 EZPZ code Codersbit
41:04 200
203 Going back to OS objective Codersbit
15:29 30
204 Longest Subarray Difference code Codersbit
69:34 200
205 MinimiZe code Codersbit
33:53 200
206 Prime Subarrays New code Codersbit
24:34 150
207 Scores code Codersbit
78:05 200
208 Shortest Path in Simple Graph objective Codersbit
3:58 30
209 Simple Queries code Codersbit
63:48 300
210 Smallest Subarray code Codersbit
32:58 250
211 The Sequence game code Codersbit
25:42 200
212 The square game code Codersbit
6:26 200
213 Three Numbers code Codersbit
47:12 200
214 Try some SQL objective Codersbit
10:22 30
215 Very Hard Queries code Codersbit
93:58 200
216 Vowels code Codersbit
58:54 250
217 Diffk code Two Pointers
27:08 300
218 Intersection Of Sorted Arrays code Two Pointers
17:34 225
219 Merge Two Sorted Lists II code Two Pointers 23:39 200
220 3 Sum code Two Pointers 55:29 225
221 Remove Duplicates from Sorted Array code Two Pointers 29:53 250
222 Sort by Color code Two Pointers
21:06 325
223 Array 3 Pointers code Two Pointers
47:26 400
224 Container With Most Water code Two Pointers
43:08 400
225 3 Sum Zero code Two Pointers
48:23 225
226 Remove Duplicates from Sorted Array II code Two Pointers 29:40 250
227 Remove Element from Array code Two Pointers 25:47 250
228 Max Continuous Series of 1s code Two Pointers 68:51 300
229 Counting Triangles code Two Pointers
51:00 225
230 Minimize the absolute difference code Two Pointers
54:09 200
231 Excel Column Number code Math 23:04 175
232 Excel Column Title code Math 38:54 175
233 FizzBuzz code Math
11:57 200
234 Greatest Common Divisor code Math 10:50 200
235 Grid Unique Paths code Math 32:00 375
236 Largest Coprime Divisor code Math
43:53 250
237 Numbers of length N and value less than K code Math
81:13 200
238 Palindrome Integer code Math
HCL
17:19 200
239 Power Of Two Integers code Math 37:55 250
240 Prime Sum code Math 42:08 150
241 Rearrange Array code Math
47:54 250
242 Reverse integer code Math 27:44 200
243 Sorted Permutation Rank code Math 66:30 250
244 Sorted Permutation Rank with Repeats code Math 65:55 500
245 Sum of pairwise Hamming Distance code Math
56:21 200
246 Trailing Zeros in Factorial code Math 18:14 250
247 AMORTIZED1 objective Time Complexity
3:03 100
248 CHOOSE1 objective Time Complexity
1:43 50
249 CHOOSE2 objective Time Complexity
2:23 80
250 CHOOSE3 objective Time Complexity
1:39 50
251 CHOOSE4 objective Time Complexity
0:57 50
252 GCD_CMPL objective Time Complexity
4:13 150
253 LOOP_CMPL objective Time Complexity
2:43 20
254 LOOP_CMPL2 objective Time Complexity
2:43 80
255 NESTED_CMPL objective Time Complexity
1:10 20
256 NESTED_CMPL2 objective Time Complexity
1:25 30
257 NESTED_CMPL3 objective Time Complexity
3:56 80
258 REC_CMPL1 objective Time Complexity
6:58 80
259 REC_CMPL2 objective Time Complexity
6:25 80
260 REC_CMPL3 objective Time Complexity
4:39 150
261 WHILE_CMPL objective Time Complexity
1:31 50
262 Add One To Number code Arrays
43:43 225
263 Anti Diagonals code Arrays 39:11 225
264 Find Duplicate in Array code Arrays 39:12 450
265 Find Permutation code Arrays
48:03 300
266 First Missing Integer code Arrays 63:31 300
267 Flip code Arrays 72:46 400
268 Hotel Bookings Possible code Arrays 60:15 225
269 Kth Row of Pascal's Triangle code Arrays
27:37 225
270 Largest Number code Arrays 69:54 225
271 Max Distance code Arrays 63:12 250
272 Max Non Negative SubArray code Arrays
57:44 150
273 Max Sum Contiguous Subarray code Arrays 33:39 225
274 Maximum Absolute Difference code Arrays
63:07 250
275 Maximum Consecutive Gap code Arrays 51:15 450
276 Maximum Unsorted Subarray code Arrays
57:35 250
277 MAXSPPROD code Arrays
73:29 200
278 Merge Intervals code Arrays
77:21 225
279 Merge Overlapping Intervals code Arrays
45:23 225
280 Min Steps in Infinite Grid code Arrays 37:51 150
281 N/3 Repeat Number code Arrays
62:13 600
282 Next Permutation code Arrays 57:43 300
283 Noble Integer code Arrays
41:31 200
284 Pascal Triangle code Arrays 26:20 225
285 Repeat and Missing Number Array code Arrays 62:41 350
286 Rotate Matrix code Arrays 57:35 300
287 Set Matrix Zeros code Arrays 46:41 300
288 Spiral Order Matrix II code Arrays 45:51 225
289 Triplets with Sum between given range code Arrays
72:41 200
290 Wave Array code Arrays 22:05 225
291 Add Two Numbers as Lists code Linked Lists 40:38 250
292 Insertion Sort List code Linked Lists
42:34 300
293 K reverse linked list code Linked Lists 50:21 200
294 List Cycle code Linked Lists 37:35 600
295 Merge Two Sorted Lists code Linked Lists
26:59 300
296 Palindrome List code Linked Lists 44:18 200
297 Partition List code Linked Lists
44:45 275
298 Remove Duplicates from Sorted List code Linked Lists 16:56 300
299 Remove Duplicates from Sorted List II code Linked Lists 51:58 300
300 Remove Nth Node from List End code Linked Lists 25:51 350
301 Reorder List code Linked Lists 52:14 600
302 Reverse Link List II code Linked Lists 54:36 450
303 Rotate List code Linked Lists 31:01 350
304 Sort List code Linked Lists
48:46 350
305 Swap List Nodes in pairs code Linked Lists
30:36 350
306 2 Sum code Hashing 44:11 300
307 4 Sum code Hashing 56:12 325
308 Anagrams code Hashing 42:03 350
309 Colorful Number code Hashing 40:27 150
310 Copy List code Hashing 46:21 450
311 Diffk II code Hashing
25:54 375
312 Equal code Hashing
61:38 350
313 Fraction code Hashing 68:58 450
314 Largest Continuous Sequence Zero Sum code Hashing
58:10 200
315 Longest Substring Without Repeat code Hashing 44:34 350
316 Points on the Straight Line code Hashing 64:18 450
317 Substring Concatenation code Hashing
62:57 1000
318 Valid Sudoku code Hashing 42:37 325
319 Window String code Hashing 68:11 350
320 Black Shapes code Graph Data Structure & Algorithms 42:18 300
321 Capture Regions on Board code Graph Data Structure & Algorithms
51:24 500
322 Clone Graph code Graph Data Structure & Algorithms 46:08 500
323 Commutable Islands code Graph Data Structure & Algorithms 61:40 200
324 Convert Sorted List to Binary Search Tree code Graph Data Structure & Algorithms
35:33 300
325 Knight On Chess Board code Graph Data Structure & Algorithms 54:22 300
326 Largest Distance between nodes of a Tree code Graph Data Structure & Algorithms
66:00 200
327 Level Order code Graph Data Structure & Algorithms 25:55 300
328 Possibility of finishing all courses given pre-requisites code Graph Data Structure & Algorithms 52:56 200
329 Smallest Multiple With 0 and 1 code Graph Data Structure & Algorithms 76:20 300
330 Smallest sequence with given Primes code Graph Data Structure & Algorithms 52:53 200
331 Stepping Numbers code Graph Data Structure & Algorithms 45:04 300
332 Sum Of Fibonacci Numbers code Graph Data Structure & Algorithms
43:00 300
333 Valid Path code Graph Data Structure & Algorithms 75:53 200
334 Word Ladder I code Graph Data Structure & Algorithms 51:47 600
335 Word Ladder II code Graph Data Structure & Algorithms 64:52 800
336 Word Search Board code Graph Data Structure & Algorithms 42:45 500
337 Add Binary Strings code Strings
37:30 300
338 Atoi code Strings 48:48 250
339 Compare Version Numbers code Strings 59:10 225
340 Count And Say code Strings
39:37 250
341 Implement StrStr code Strings 31:49 225
342 Integer To Roman code Strings 37:35 250
343 Justified Text code Strings
69:16 300
344 Length of Last Word code Strings 17:39 225
345 Longest Common Prefix code Strings
26:21 225
346 Longest Palindromic Substring code Strings 54:32 500
347 Minimum Characters required to make a String Palindromic code Strings
56:37 200
348 Multiply Strings code Strings
54:25 375
349 Palindrome String code Strings
30:06 150
350 Power of 2 code Strings 54:47 350
351 Pretty Json code Strings
55:11 400
352 Reverse the String code Strings 35:44 250
353 Roman To Integer code Strings 30:57 250
354 Stringoholics code Strings
70:09 300
355 Valid Ip Addresses code Strings 53:24 250
356 Valid Number code Strings 51:58 250
357 Zigzag String code Strings
48:01 300
358 Design Cache subjective Storage Scalability 40:00 200
359 Highly Available Database subjective Storage Scalability 50:00 400
360 Highly Consistent Database subjective Storage Scalability
50:00 400
361 Sharding a Database subjective Storage Scalability 35:00 200