2020 leetcode problem statistics

I made a simple statistics on 2020 leetcode problems. A few old problems are also included.
classification are made roughly based on the problem most important features.

• dp, 80
• greedy 64
• backtracking 11
• dfs 8
• bfs 9
• union find 8
• stack, queue, deque 12
• heap 9
• hashmap 29
• tree 42
• linked-list 5
• sliding window 15
• sort 5
• string 8
• array 50
• math 38
• strategy game 38
• linear programming 3
• graph 14
• intervals 8
• recursive 5
• bits 10
• Trie 4
• misc 9
  As we see, dp is the most frequent problems, followed by greedy.
  Among the alogrithms, backtracking, bfs/dfs, union-find, sliding window, strategy game are also very common.
  Among the data structures, tree and array are most common, and hashmap, heap are also very common.

dp, 80

1387 Sort Integers by The Power Value 70.6% Medium
1483 Kth Ancestor of a Tree Node 29.5% Hard
1186 Maximum Subarray Sum with One Deletion 38.3% Medium
1191 K-Concatenation Maximum Sum 25.4% Medium
1235 Maximum Profit in Job Scheduling 46.0% Hard
1239 Maximum Length of a Concatenated String with Unique Characters 48.7% Medium
1240 Tiling a Rectangle with the Fewest Squares 51.3% Hard
1246 Palindrome Removal 45.7% Hard
1278 Palindrome Partitioning III 60.2% Hard
1326 Minimum Number of Taps to Open to Water a Garden 45.7% Hard
1335 Minimum Difficulty of a Job Schedule 58.5% Hard
1340 Jump Game V 58.3% Hard
1363 Largest Multiple of Three 33.7% Hard
1262 Greatest Sum Divisible by Three 48.4% Medium
1388 Pizza With 3n Slices 45.0% Hard
1402 Reducing Dishes 72.3% Hard
1449 Form Largest Integer With Digits That Add up to Target 43.1% Hard
1458 Max Dot Product of Two Subsequences 42.5% Hard
1473 Paint House III 48.7% Hard
1478 Allocate Mailboxes 55.1% Hard
1531 String Compression II 32.2% Hard
1548 The Most Similar Path in a Graph 55.3% Hard
1425 Constrained Subsequence Sum 44.6% Hard

1696. Jump Game Vi.
      1553 Minimum Number of Days to Eat N Oranges 28.6% Hard
      1611 Minimum One Bit Operations to Make Integers Zero 56.6% Hard
      1230 Toss Strange Coins 49.3% Medium
      1463 Cherry Pickup II 66.2% Hard
      1320 Minimum Distance to Type a Word Using Two Fingers 62.6% Hard
      1547 Minimum Cost to Cut a Stick 51.2% Hard
      1397 Find All Good Strings 37.9% Hard
      1269 Number of Ways to Stay in the Same Place After Some Steps 43.1% Hard
      1259 Handshakes That Don't Cross 53.9% Hard
      1220 Count Vowels Permutation 53.8% Hard
      1416 Restore The Array 36.2% Hard
      1359 Count All Valid Pickup and Delivery Options 57.1% Hard
      1575 Count All Possible Routes 58.4% Hard
      1444 Number of Ways of Cutting a Pizza 53.4% Hard
      1524 Number of Sub-arrays With Odd Sum 38.9% Medium
      1301 Number of Paths with Max Score 37.7% Hard
      1621 Number of Sets of K Non-Overlapping Line Segments 41.3% Medium
      1569 Number of Ways to Reorder Array to Get Same BST 50.0% Hard
1697. Palindromic Substrings
      1411 Number of Ways to Paint N × 3 Grid 60.6% Hard
1698. Count ways to distribute candies
      1155 Number of Dice Rolls With Target Sum 47.7% Medium
      1223 Dice Roll Simulation 46.8% Medium
1699. Count Different Palindromic Subsequences
      1504 Count Submatrices With All Ones 61.5% Medium
      1292 Maximum Side Length of a Square with Sum Less than or Equal to Threshold 49.9% Medium
      1594 Maximum Non Negative Product in a Matrix 31.9% Medium
      1162 As Far from Land as Possible 44.3% Medium
      1277 Count Square Submatrices with All Ones 73.0% Medium
      1289 Minimum Falling Path Sum II 61.8% Hard
      1314 Matrix Block Sum 73.6% Medium
1700. Longest palindromic subsequence II
      516 Longest Palindromic Subsequence 54.4% Medium
1701. Longest Palindromic Substring
1702. Edit Distance
1703. Delete operation for two strings
1704. Minimum ASCII delete sum for two strings
      1216 Valid Palindrome III 48.8% Hard
      1312 Minimum Insertion Steps to Make a String Palindrome 58.8% Hard
1705. longest common subsequence
1706. Uncrossed lines
      1218 Longest Arithmetic Subsequence of Given Difference 45.9% Medium
      1187 Make Array Strictly Increasing 41.5% Hard
      1626 Best Team With No Conflicts 36.7% Medium
1707. Minimum Number of Removals to Make Mountain Array
1708. Maximum Height by stacking cuboids
1709. Burst Balloons
      1641 Count Sorted Vowel Strings
      1639 Number of Ways to Form a Target String Given a Dictionary 38.9% Hard
      1542 Find Longest Awesome Substring 36.0% Hard
      1349 Maximum Students Taking Exam 43.3% Hard
      1434 Number of Ways to Wear Different Hats to Each Other 38.9% Hard
      1494 Parallel Courses II 31.0% Hard
      1595 Minimum Cost to Connect Two Groups of Points 41.9% Hard
      1659 Maximize Grid Happiness 29.1% Hard

greedy 64

1153 String Transforms Into Another String 35.9% Hard
1183 Maximum Number of Ones 56.1% Hard
1199 Minimum Time to Build Blocks 38.0% Hard
1167 Minimum Cost to Connect Sticks 63.8% Medium
1217 Minimum Cost to Move Chips to The Same Position 71.2% Easy
1234 Replace the Substring for Balanced String 34.1% Medium
1247 Minimum Swaps to Make Strings Equal 62.2% Medium
1253 Reconstruct a 2-Row Binary Matrix 41.2% Medium
1266 Minimum Time Visiting All Points 79.2% Easy
1282 Group the People Given the Group Size They Belong To 84.2% Medium
1296 Divide Array in Sets of K Consecutive Numbers 54.9% Medium
1297 Maximum Number of Occurrences of a Substring 48.9% Medium
1328 Break a Palindrome 45.1% Medium
1374 Generate a String With Characters That Have Odd Counts 76.1% Easy
1403 Minimum Subsequence in Non-Increasing Order 71.3% Easy

1702. Max binary string after change
      1432 Max Difference You Can Get From Changing an Integer 42.9% Medium
      1433 Check If a String Can Break Another String 66.9% Medium
      1481 Least Number of Unique Integers after K Removals 55.2% Medium
      1503 Last Moment Before All Ants Fall Out of a Plank 52.6% Medium
      1227 Airplane Seat Assignment Probability 61.8% Medium
      1509 Minimum Difference Between Largest and Smallest Value in Three Moves 51.6% Medium
      1561 Maximum Number of Coins You Can Get 78.9% Medium
      1526 Minimum Number of Increments on Subarrays to Form a Target Array 59.3% Hard
      1529 Bulb Switcher IV 70.7% Medium
      1536 Minimum Swaps to Arrange a Binary Grid 42.8% Medium
      1538 Guess the Majority in a Hidden Array 61.3% Medium
      1541 Minimum Insertions to Balance a Parentheses String 41.9% Medium
      1540 Can Convert String in K Moves 29.6% Medium
1703. Smallest range I.
1704. Smallest Range II
      1551 Minimum Operations to Make Array Equal 77.8% Medium
      1558 Minimum Numbers of Function Calls to Make Target Array 62.4% Medium
      1576 Replace All ?'s to Avoid Consecutive Repeating Characters 48.0% Easy
      1578 Minimum Deletion Cost to Avoid Repeating Letters 60.1% Medium
      1579 Remove Max Number of Edges to Keep Graph Fully Traversable 45.5% Hard
      1564 Put Boxes Into the Warehouse I 66.2% Medium
      1580 Put Boxes Into the Warehouse II 63.0% Medium
      1585 Check If String Is Transformable With Substring Sort Operations 48.0% Hard
      1589 Maximum Sum Obtained of Any Permutation 34.5% Medium
      1591 Strange Printer II 55.1% Hard
      1599 Maximum Profit of Operating a Centennial Wheel 43.2% Medium
      1605 Find Valid Matrix Given Row and Column Sums 76.9% Medium
1705. Minimum Deletions to Make Character Frequencies Unique
1706. Minimize Deviation in Array
1707. Find the most competitive subsequence
      1665 Minimum Initial Energy to finish tasks
      1663 Smallest string with a given numeric value
      1150 Check If a Number Is Majority Element in a Sorted Array 58.3% Easy
      1157 Online Majority Element In Subarray 39.3% Hard
      1182 Shortest Distance to Target Color 53.2% Medium
      1231 Divide Chocolate 53.1% Hard
      1283 Find the Smallest Divisor Given a Threshold 48.9% Medium
      1300 Sum of Mutated Array Closest to Target 43.5% Medium
      1351 Count Negative Numbers in a Sorted Matrix 76.0% Easy
      1482 Minimum Number of Days to Make m Bouquets 48.8% Medium
      1533 Find the Index of the Large Integer 55.1% Medium
      1539 Kth Missing Positive Number 53.4% Easy
      1552 Magnetic Force Between Two Balls 48.2% Medium
      1574 Shortest Subarray to be Removed to Make Array Sorted 31.9% Medium
      1618 Maximum Font to Fit a Sentence in a Screen 57.5% Medium
1708. Path with minimum effort
      1648 Sell Diminishing-Valued Colored Balls 30.4% Medium
1709. Min moves to make array complimentary

backtracking 11

1215 Stepping Numbers 42.7% Medium
1258 Synonymous Sentences 67.2% Medium
1286 Iterator for Combination 70.7% Medium
1291 Sequential Digits 57.4% Medium
1307 Verbal Arithmetic Puzzle 37.6% Hard
1467 Probability of a Two Boxes Having The Same Number of Distinct Balls 61.3% Hard
1593 Split a String Into the Max Number of Unique Substrings 46.7% Medium
1601 Maximum Number of Achievable Transfer Requests 47.2% Hard

131. Palindrome Partitioning
     1655 Distribute Repeating Integers 40.0% Hard
132. Minimum Incompatibility

dfs 8

1219 Path with Maximum Gold 65.6% Medium
1254 Number of Closed Islands 61.1% Medium
1306 Jump Game III 60.5% Medium
1377 Frog Position After T Seconds 34.2% Hard
1462 Course Schedule IV 43.9% Medium
1559 Detect Cycles in 2D Grid 44.8% Hard
1568 Minimum Number of Days to Disconnect Island 51.1% Hard
1600 Throne Inheritance 58.8% Medium

bfs 9

1197 Minimum Knight Moves 36.7% Medium
1210 Minimum Moves to Reach Target with Rotations 45.9% Hard
1263 Minimum Moves to Move a Box to Their Target Location 42.4% Hard
1284 Minimum Number of Flips to Convert Binary Matrix to Zero Matrix 69.8% Hard
1293 Shortest Path in a Grid with Obstacles Elimination 42.8% Hard
1298 Maximum Candies You Can Get from Boxes 59.5% Hard
1391 Check if There is a Valid Path in a Grid 45.0% Medium

1706. Where will the ball fall
      1654 Minimum Jumps to Reach Home 28.0% Medium

union find 8

1202 Smallest String With Swaps 47.5% Medium
1319 Number of Operations to Make Network Connected 54.6% Medium
1489 Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree 52.2% Hard

1697. Checking existence of edge length limited paths
      1562 Find Latest Group of Size M 39.0% Medium
      1627 Graph Connectivity With Threshold 36.9% Hard
      1331 Rank Transform of an Array 57.9% Easy
1698. Rank transform of a matrix

stack, queue, deque 12

84 Largest Rectangle in Histogram 36.0% Hard
1209 Remove All Adjacent Duplicates in String II 57.4% Medium
1221 Split a String in Balanced Strings 83.8% Easy
1249 Minimum Remove to Make Valid Parentheses 63.2% Medium
1309 Decrypt String from Alphabet to Integer Mapping 77.3% Easy
1381 Design a Stack With Increment Operation 75.9% Medium
1441 Build an Array With Stack Operations 69.3% Easy
1475 Final Prices With a Special Discount in a Shop 75.0% Easy
1597 Build Binary Expression Tree From Infix Expression 63.6% Hard
1628 Design an Expression Tree With Evaluate Function 86.0% Medium
1190 Reverse Substrings Between Each Pair of Parentheses 63.8% Medium
1700 number of students unable to eat lunch

heap 9

1353 Maximum Number of Events That Can Be Attended 29.7% Medium
1354 Construct Target Array With Multiple Sums 31.3% Hard
1383 Maximum Performance of a Team 34.0% Hard
1405 Longest Happy String 51.7% Medium

1705. Max number of eaten apple
      1438 Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit 43.5% Medium
      1439 Find the Kth Smallest Sum of a Matrix With Sorted Rows 60.0% Hard
      1499 Max Value of Equation 44.9% Hard
1706. furthest building you can reach

hashmap 29

1152 Analyze User Website Visit Pattern 43.2% Medium
1166 Design File System 57.8% Medium
1169 Invalid Transactions 31.5% Medium
1171 Remove Zero Sum Consecutive Nodes from Linked List 41.4% Medium
1172 Dinner Plate Stacks 38.0% Hard
1181 Before and After Puzzle 44.4% Medium
1224 Maximum Equal Frequency 34.2% Hard
1329 Sort the Matrix Diagonally 79.3% Medium
1338 Reduce Array Size to The Half 66.8% Medium
1347 Minimum Number of Steps to Make Two Strings Anagram 75.3% Medium
1348 Tweet Counts Per Frequency 31.5% Medium
1370 Increasing Decreasing String 76.2% Easy
1395 Count Number of Teams 82.1% Medium
1396 Design Underground System 67.5% Medium
1418 Display Table of Food Orders in a Restaurant 67.6% Medium
1426 Counting Elements 58.9% Easy
1429 First Unique Number 48.4% Medium
1460 Make Two Arrays Equal by Reversing Sub-arrays 72.5% Easy
1477 Find Two Non-overlapping Sub-arrays Each With Target Sum 33.4% Medium
1496 Path Crossing 55.7% Easy
1487 Making File Names Unique 30.0% Medium
1488 Avoid Flood in The City 24.9% Medium
1500 Design a File Sharing System 45.1% Medium
1512 Number of Good Pairs 88.0% Easy
1525 Number of Good Ways to Split a String 67.2% Medium
1577 Number of Ways Where Square of Number Is Equal to Product of Two Numbers 37.0% Medium
1567 Maximum Length of Subarray With Positive Product 36.0% Medium
1590 Make Sum Divisible by P 27.2% Medium
1604 Alert Using Same Key-Card Three or More Times in a One Hour Period 41.4% Medium

tree 42

1161 Maximum Level Sum of a Binary Tree 71.1% Medium
1214 Two Sum BSTs 67.8% Medium
1245 Tree Diameter 61.1% Medium
1261 Find Elements in a Contaminated Binary Tree 74.3% Medium
1273 Delete Tree Nodes 63.3% Medium
1302 Deepest Leaves Sum 83.9% Medium
1305 All Elements in Two Binary Search Trees 77.7% Medium
1315 Sum of Nodes with Even-Valued Grandparent 83.8% Medium
1325 Delete Leaves With a Given Value 73.4% Medium
1339 Maximum Product of Splitted Binary Tree 37.4% Medium
1361 Validate Binary Tree Nodes 44.9% Medium
1367 Linked List in Binary Tree 41.1% Medium
1372 Longest ZigZag Path in a Binary Tree 54.4% Medium
1373 Maximum Sum BST in Binary Tree 38.1% Hard
1379 Find a Corresponding Node of a Binary Tree in a Clone of That Tree 84.0% Medium
1382 Balance a Binary Search Tree 75.7% Medium
1430 Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree 45.0% Medium
1443 Minimum Time to Collect All Apples in a Tree 54.6% Medium
1448 Count Good Nodes in Binary Tree 70.2% Medium
1457 Pseudo-Palindromic Paths in a Binary Tree 67.9% Medium
1469 Find All The Lonely Nodes 80.8% Easy
1485 Clone Binary Tree With Random Pointer 80.1% Medium
1490 Clone N-ary Tree 83.7% Medium
1506 Find Root of N-Ary Tree 80.5% Medium
1516 Move Sub-Tree of N-Ary Tree 62.1% Hard
1519 Number of Nodes in the Sub-Tree With the Same Label 36.2% Medium
1522 Diameter of N-Ary Tree 68.5% Medium
1530 Number of Good Leaf Nodes Pairs 55.2% Medium
1572 Matrix Diagonal Sum 78.3% Easy
1586 Binary Search Tree Iterator II 65.6% Medium
1602 Find Nearest Right Node in Binary Tree 75.0% Medium
1609 Even Odd Tree 54.0% Medium
1612 Check If Two Expression Trees are Equivalent 71.0% Medium
1660 Correct a Binary Tree 83.2% Medium

235. Lowest Common Ancestor of a Binary Search Tree
     1257 Smallest Common Region 60.0% Medium
236. Lowest Common Ancestor of a Binary Tree
     1644 Lowest Common Ancestor of a Binary Tree II 59.7% Medium
237. Lowest Common Ancestor of a Binary Tree III
238. Lowest Common Ancestor of a Binary Tree IV
     1666 Change the root of a binary tree
     1649 Create Sorted Array through Instructions 42.0% Hard

linked-list 5

1206 Design Skiplist 57.9% Hard
1265 Print Immutable Linked List in Reverse 94.5% Medium
1474 Delete N Nodes After M Nodes of a Linked List 74.4% Easy
1669 Merge in between linked list

1634. Add Two Polynomials Represented as Linked Lists

sliding window 15

1151 Minimum Swaps to Group All 1's Together 58.7% Medium
1156 Swap For Longest Repeated Character Substring 47.7% Medium
1163 Last Substring in Lexicographical Order 35.7% Hard
1176 Diet Plan Performance 53.9% Easy
1208 Get Equal Substrings Within Budget 42.9% Medium
1248 Count Number of Nice Subarrays 56.6% Medium
1343 Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold 64.3% Medium
1352 Product of the Last K Numbers 42.6% Medium
1358 Number of Substrings Containing All Three Characters 60.0% Medium

1703. Min adjacent swaps for k consecutive ones.
      1423 Maximum Points You Can Obtain from Cards 45.1% Medium
      1456 Maximum Number of Vowels in a Substring of Given Length 53.5% Medium
      1461 Check If a String Contains All Binary Codes of Size K 46.3% Medium
      1493 Longest Subarray of 1's After Deleting One Element 58.6% Medium
1704. Maximum Erasure value.

sort 5

1333 Filter Restaurants by Vegan-Friendly, Price and Distance 56.9% Medium
1337 The K Weakest Rows in a Matrix 69.5% Easy
1366 Rank Teams by Votes 54.5% Medium
1451 Rearrange Words in a Sentence 58.4% Medium
1471 The k Strongest Values in an Array 58.3% Medium

string 8

1233 Remove Sub-Folders from the Filesystem 61.2% Medium
1316 Distinct Echo Substrings 49.4% Hard
1323 Maximum 69 Number 77.9% Easy
1392 Longest Happy Prefix 41.1% Hard
1400 Construct K Palindrome Strings 62.5% Medium
1404 Number of Steps to Reduce a Number in Binary Representation to One 50.5% Medium
1408 String Matching in an Array 62.6% Easy
1410 HTML Entity Parser 54.3% Medium

array 50

1177 Can Make Palindrome from Substring 35.7% Medium
1200 Minimum Absolute Difference 66.6% Easy
1213 Intersection of Three Sorted Arrays 79.0% Easy
1198 Find Smallest Common Element in All Rows 74.9% Medium
1222 Queens That Can Attack the King 69.0% Medium
1260 Shift 2D Grid 61.5% Easy
1267 Count Servers that Communicate 57.6% Medium
1275 Find Winner on a Tic Tac Toe Game 52.8% Easy
1287 Element Appearing More Than 25% In Sorted Array 60.2% Easy
1299 Replace Elements with Greatest Element on Right Side 74.6% Easy
1324 Print Words Vertically 58.7% Medium
1375 Bulb Switcher III 63.9% Medium
1409 Queries on a Permutation With Key 81.2% Medium
1424 Diagonal Traverse II 44.6% Medium
1534 Count Good Triplets 79.9% Easy
1428 Leftmost Column with at Least a One 48.2% Medium
1427 Perform String Shifts 53.3% Easy
1437 Check If All 1's Are at Least Length K Places Away 61.9% Medium
1446 Consecutive Characters 61.8% Easy
1455 Check If a Word Occurs As a Prefix of Any Word in a Sentence 65.0% Easy
1464 Maximum Product of Two Elements in an Array 77.0% Easy
1472 Design Browser History 68.8% Medium
1498 Number of Subsequences That Satisfy the Given Sum Condition 37.9% Medium
1508 Range Sum of Sorted Subarray Sums 63.0% Medium
1513 Number of Substrings With Only 1s 40.9% Medium
1554 Strings Differ by One Character 63.1% Medium
1560 Most Visited Sector in a Circular Track 56.9% Easy
1573 Number of Ways to Split a String 30.4% Medium
1582 Special Positions in a Binary Matrix 64.3% Easy
1583 Count Unhappy Friends 52.6% Medium
1588 Sum of All Odd Length Subarrays 81.1% Easy
1592 Rearrange Spaces Between Words 43.8% Easy
1606 Find Servers That Handled Most Number of Requests 36.0% Hard
1608 Special Array With X Elements Greater Than or Equal X 62.4% Easy
1610 Maximum Number of Visible Points 27.3% Hard
1614 Maximum Nesting Depth of the Parentheses 84.4% Easy
1616 Split Two Strings to Make Palindrome 36.5% Medium

1685. Sum of absolute differences in a sorted array
1686. Arithmetic subarrays
1687. Widest Vertical Area Between Two Points Containing No Points
1688. Sort Array by Increasing Frequency
1689. Count Substrings That Differ by One Character
1690. Kth Smallest Instructions
1691. Defuse the bomb.
      1653 Minimum Deletions to Make String Balanced 46.5% Medium
      1664 ways to make a fair array
      1662 Check if two string arrays are equivalent
      1658 Minimum Operations to Reduce X to Zero 29.3% Medium
      1657 Determine if Two Strings Are Close 50.0% Medium
      1643 Kth Smallest Instructions 41.7% Hard
      1625 Lexicographically Smallest String After Applying Operations 62.6% Medium

math 38

1175 Prime Arrangements 51.5% Easy
1185 Day of the Week 62.5% Easy
1189 Maximum Number of Balloons 61.7% Easy
1201 Ugly Number III 26.2% Medium
1232 Check If It Is a Straight Line 44.3% Easy
1250 Check If It Is a Good Array 56.1% Hard
1276 Number of Burgers with No Waste of Ingredients 50.0% Medium
1330 Reverse Subarray To Maximize Array Value 35.9% Hard
1344 Angle Between Hands of a Clock 61.3% Medium
1362 Closest Divisors 57.3% Medium
1390 Four Divisors 38.8% Medium
1401 Circle and Rectangle Overlapping 42.3% Medium
1413 Minimum Value to Get Positive Step by Step Sum 65.1% Easy
1422 Maximum Score After Splitting a String 55.9% Easy
1492 The kth Factor of n 65.9% Medium
1515 Best Position for a Service Centre 36.5% Hard
1447 Simplified Fractions 61.6% Medium
1453 Maximum Number of Darts Inside of a Circular Dartboard 34.7% Hard
1465 Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts 31.3% Medium
1497 Check If Array Pairs Are Divisible by k 40.3% Medium
1622 Fancy Sequence 15.8% Hard
1620 Coordinate With Maximum Network Quality 37.7% Medium

1480. running sum of 1d array *
1481. kids with greatest number of candies *
1482. shuffle the array *
1483. decompress run-length encoded list *
1484. number of good pairs **
1485. create target array in the given order **
1486. find numbers with even number of digits **
1487. Find N Unique Integers Sum up to Zero *
1488. Make Two Arrays Equal by Reversing Sub-arrays **
1489. flipping an image *
1490. Can Make Arithmetic Progression From Sequence **
1491. Replace Elements with Greatest Element on Right Side **
1492. Lucky Numbers in a Matrix **
1493. height checker *
1494. Average Salary Excluding the Minimum and Maximum Salary *
1495. Find Common Characters **

strategy game 38

1406 Stone Game III 56.8% Hard
1510 Stone Game IV 58.5% Hard
679 24 Game 47.0% Hard
1510 Stone Game IV 58.6% Hard
1025 Divisor Game 66.1% Easy
837 New 21 Game 35.3% Medium
877 Stone Game 66.1% Medium
1563 Stone Game V 40.1% Hard

1686. Stone game IV
      682 Baseball Game 65.6% Easy
      293 Flip Game 61.1% Easy
      294 Flip Game II 50.5% Medium
      292 Nim Game 54.9% Easy
      1140 Stone Game II 64.8% Medium
      488 Zuma Game 38.8% Hard
      55 jump game
1687. Jump game II.
1688. Dungeon Game
1689. Game of life
1690. Elimination game
1691. Jump Game IV
1692. Jump Game V.
1693. design snake game
1694. Stone game VII
1695. Stone game III
1696. Chalkboard XOR game.
1697. Card flipping game
1698. Jump Game III
1699. Binary tree coloring game
1700. Find the winner of an array game
1701. Find winner on a tic tac toe game
1702. Moving Stones Until Consecutive II
1703. guess number higher or lower II
1704. Guess number higher or lower
1705. Can I win

linear programming 3

1626 Best Team With No Conflicts 36.7% Medium
1687. Delivering boxes from storage to ports
1642 Furthest Building You Can Reach 54.7% Medium

graph 14

1168 Optimize Water Distribution in a Village 62.1% Hard
1192 Critical Connections in a Network 49.4% Hard
1203 Sort Items by Groups Respecting Dependencies 48.6% Hard
1311 Get Watched Videos by Your Friends 43.8% Medium
1334 Find the City With the Smallest Number of Neighbors at a Threshold Distance 46.0% Medium
1368 Minimum Cost to Make at Least One Valid Path in a Grid 55.8% Hard
1376 Time Needed to Inform All Employees 56.2% Medium
1436 Destination City 77.2% Easy
1466 Reorder Routes to Make All Paths Lead to the City Zero 61.5% Medium
1514 Path with Maximum Probability 38.5% Medium
1557 Minimum Number of Vertices to Reach All Nodes 74.3% Medium
1584 Min Cost to Connect All Points 49.0% Medium
1615 Maximal Network Rank 51.3% Medium
1617 Count Subtrees With Max Distance Between Cities 63.0% Hard

intervals 8

1229 Meeting Scheduler 53.8% Medium
1272 Remove Interval 57.8% Medium
1288 Remove Covered Intervals 57.1% Medium
1419 Minimum Number of Frogs Croaking 46.9% Medium

1701. Average waiting time
      1450 Number of Students Doing Homework at a Given Time 77.1% Easy
      1520 Maximum Number of Non-Overlapping Substrings 34.8% Hard
      1546 Maximum Number of Non-Overlapping Subarrays With Sum Equals Target 43.5% Medium

recursive 5

1274 Number of Ships in a Rectangle 65.6% Hard
1414 Find the Minimum Number of Fibonacci Numbers Whose Sum Is K 63.5% Medium
1415 The k-th Lexicographical String of All Happy Strings of Length n 69.9% Medium
1545 Find Kth Bit in Nth Binary String 57.0% Medium
1537 Get the Maximum Score 36.1% Hard

bits 10

1238 Circular Permutation in Binary Representation 65.4% Medium
1255 Maximum Score Words Formed by Letters 69.6% Hard
1310 XOR Queries of a Subarray 68.9% Medium
1318 Minimum Flips to Make a OR b Equal to c 63.5% Medium
1371 Find the Longest Substring Containing Vowels in Even Counts 61.4% Medium
1386 Cinema Seat Allocation 35.2% Medium
1442 Count Triplets That Can Form Two Arrays of Equal XOR 70.5% Medium
1452 People Whose List of Favorite Companies Is Not a Subset of Another List 54.3% Medium
1486 XOR Operation in an Array 84.0% Easy
1521 Find a Value of a Mysterious Function Closest to Target 43.7% Hard

Trie 4

1178 Number of Valid Words for Each Puzzle 38.4% Hard
1268 Search Suggestions System 64.4% Medium

1707. Maximum XOR with an element from array.
1708. Number of distinct substrings in a string.

misc 9

1154 Day of the Year 49.3% Easy
1236 Web Crawler 64.3% Medium
1237 Find Positive Integer Solution for a Given Equation 69.6% Easy
1244 Design A Leaderboard 64.6% Medium
1243 Array Transformation 50.6% Easy
1256 Encode Number 67.0% Medium
1360 Number of Days Between Two Dates 47.4% Easy
1505 Minimum Possible Integer After at Most K Adjacent Swaps On Digits 36.1% Hard
1420 Build Array Where You Can Find The Maximum Exactly K Comparisons 64.4% Hard