Year
2026 archive
A year-sized slice of the daily archive, ordered newest first.
168 entries
168 entries from 2026.
23.06.2026
hard3699. Number of ZigZag Arrays I
Ways to make l..r zigzag sequence
22.06.2026
easy1189. Maximum Number of Balloons
Count "balloon"s in stirng
21.06.2026
medium1833. Maximum Ice Cream Bars
Max count by given coins
20.06.2026
hard1840. Maximum Building Height
Max growing height with restrictions
19.06.2026
easy1732. Find the Highest Altitude
Max running sum
18.06.2026
medium1344. Angle Between Hands of a Clock
Angle between clock arrows
17.06.2026
hard3614. Process String with Special Operations II
K-th char ina pattern-build a string, %-reverse, , -pop
16.06.2026
medium3612. Process String with Special Operations I
Pattern-build a string, %-reverse, , -pop
15.06.2026
medium2095. Delete the Middle Node of a Linked List
Remove the middle of Linked LIst
14.06.2026
medium2130. Maximum Twin Sum of a Linked List
Max sum pairwise from tail
13.06.2026
easy3838. Weighted Word Mapping
Convert words to chars by weighting their sums and reversing
12.06.2026
hard3559. Number of Ways to Assign Edge Weights II
Ways to color the all queries paths a..b in tree
11.06.2026
medium3558. Number of Ways to Assign Edge Weights I
Ways to color the deepest path in tree
10.06.2026
hard3691. Maximum Total Subarray Value II
sum k largest ranges max(l..r)-min(l..r)
06.06.2026
easy2574. Left and Right Sum Differences
abs(prefix sum - suffix sum)
05.06.2026
hard3753. Total Waviness of Numbers in Range II
Count hills and valleys base10 in a..b
04.06.2026
medium3751. Total Waviness of Numbers in Range I
Count hills and valleys base10 in a..b
03.06.2026
medium3635. Earliest Finish Time for Land and Water Rides II
Min finish time of land + water single events
02.06.2026
easy3633. Earliest Finish Time for Land and Water Rides I
Min finish time of land + water single events
01.06.2026
easy2144. Minimum Cost of Buying Candies With Discount
Min sum taking 2 out of 3
31.05.2026
medium2126. Destroying Asteroids
Can consume all asteroids smaller than running sum?
30.05.2026
hard3161. Block Placement Queries
Queries 'can place a gap after place an obstacle'
29.05.2026
easy3300. Minimum Element After Replacement With Digit Sum
Min of digits sum
28.05.2026
hard3093. Longest Common Suffix Queries
Query common suffixes match
27.05.2026
medium3121. Count the Number of Special Characters II
Count sorted characters
26.05.2026
easy3120. Count the Number of Special Characters I
Count letters with both cases
25.05.2026
medium1871. Jump Game VII
Can reach end jumping min..max to zeros
24.05.2026
hard1340. Jump Game V
Max visited by jumping down in distance d
23.05.2026
easy1752. Check if Array Is Sorted and Rotated
Is array shifted and sorted?
22.05.2026
medium33. Search in Rotated Sorted Array
Binary search in shifted array
21.05.2026
medium3043. Find the Length of the Longest Common Prefix
Longest prefix of pairs
20.05.2026
medium2657. Find the Prefix Common Array of Two Arrays
Duplicates in prefixes
19.05.2026
easy2540. Minimum Common Value
Min common of two sorted list
18.05.2026
hard1345. Jump Game IV
Min steps to reach end jumping to same value or left or right
17.05.2026
medium1306. Jump Game III
Can reach 0 by jumping +a[i] - a[i]
16.05.2026
hard154. Find Minimum in Rotated Sorted Array II
Binary search in shifted array with duplicates
15.05.2026
medium153. Find Minimum in Rotated Sorted Array
Binary search in shifted array
14.05.2026
easy2784. Check if Array is Good
Is combination 1..n,n
13.05.2026
medium1674. Minimum Moves to Make Array Complementary
Min changes 1..L to make complementary pair sum equal
12.05.2026
hard1665. Minimum Initial Energy to Finish Tasks
Energy for all tasks (spend, limit)
11.05.2026
easy2553. Separate the Digits in an Array
LIst of numbers to list of digits
10.05.2026
medium2770. Maximum Number of Jumps to Reach the Last Index
Max steps to reach end by jumps n[j]-n[i] in -t..t
09.05.2026
medium1914. Cyclically Rotating a Grid
Rotate matix layers by k
08.05.2026
medium3629. Minimum Jumps to Reach End via Prime Teleportation
Shortest path by prime factors
07.05.2026
medium3660. Jump Game IX
Max on path jumping left-up and right-down
06.05.2026
medium1861. Rotating the Box
Rotate and simulate gravity in matrix
05.05.2026
medium61. Rotate List
Rotate linked list k steps
04.05.2026
medium48. Rotate Image
Rotate square matrix
03.05.2026
easy796. Rotate String
Match strings after rotation
02.05.2026
medium788. Rotated Digits
Count numbers in 0..n with mirrored digits 2-5 6-9, 0,1,8, but not 3,4,7
01.05.2026
medium396. Rotate Function
Max rolling hash
30.04.2026
medium3742. Maximum Path Score in a Grid
Max right-bottom path value with at most k cost
29.04.2026
hard3225. Maximum Score From Grid Operations
Max sum adjacent to marked columns
28.04.2026
medium2033. Minimum Operations to Make a Uni-Value Grid
Min ops to make all numbers equal by +-X
27.04.2026
medium1391. Check if There is a Valid Path in a Grid
Path 0 to end on type-cells 2D grid
26.04.2026
medium1559. Detect Cycles in 2D Grid
Check cycle in 2D grid
25.04.2026
hard3464. Maximize the Distance Between Points on a Square
Max of minimum distnace between selected k points on square perimeter
24.04.2026
easy2833. Furthest Point From Origin
Max dist when replace with L or R
23.04.2026
medium2615. Sum of Distances
Sum of distances to each occurance
22.04.2026
medium2452. Words Within Two Edits of Dictionary
Words in dictionary with 2 edits
21.04.2026
medium1722. Minimize Hamming Distance After Swap Operations
Diff src vs target after rearrange by rules
20.04.2026
easy2078. Two Furthest Houses With Different Colors
Max distance between different numbers
19.04.2026
medium1855. Maximum Distance Between a Pair of Values
Max distance a[i] not greater than b[j] window
18.04.2026
easy3783. Mirror Distance of an Integer
Diff with reversal
17.04.2026
medium3761. Minimum Absolute Distance Between Mirror Pairs
Distance to prev mirror number
16.04.2026
medium3488. Closest Equal Element Queries
Shortest distances to the same values
15.04.2026
easy2515. Shortest Distance to Target String in a Circular Array
Distance to target
14.04.2026
hard2463. Minimum Total Distance Traveled
Shortest distances to travel robots to factories
13.04.2026
easy1848. Minimum Distance to the Target Element
Distance to target from start
12.04.2026
hard1320. Minimum Distance to Type a Word Using Two Fingers
Min travel on keyboard to type a word
11.04.2026
medium3741. Minimum Distance Between Three Equal Elements II
Min sum of distances between i,j,k of the same values
10.04.2026
easy3740. Minimum Distance Between Three Equal Elements I
Min sum of distances between i,j,k of the same values
09.04.2026
hard3655. XOR After Range Multiplication Queries II
Run stepped multiplication queries
08.04.2026
medium3653. XOR After Range Multiplication Queries I
Run queries
07.04.2026
medium2069. Walking Robot Simulation II
Implement perimeter-robot
06.04.2026
medium874. Walking Robot Simulation
Farthest robot movement
05.04.2026
easy657. Robot Return to Origin
R,L,U,D return to 0 in XY plane
04.04.2026
medium2075. Decode the Slanted Ciphertext
Decode row-encoded string
03.04.2026
hard3661. Maximum Walls Destroyed by Robots
Max walls hit, each robot shoot left or right
02.04.2026
medium3418. Maximum Amount of Money Robot Can Earn
Max sum path, 2 skips allowed
01.04.2026
hard2751. Robot Collisions
Collide LR robots
31.03.2026
hard3474. Lexicographically Smallest Generated String
String from pattern matches
30.03.2026
medium2840. Check if Strings Can be Made Equal With Operations II
Strings equal at odd-even positions
29.03.2026
easy2839. Check if Strings Can be Made Equal With Operations I
Match a and b at (0|2,1|3) positions
28.03.2026
hard2573. Find the String with LCP
Build string from longest common prefixes matrix
27.03.2026
easy2946. Matrix Similarity After Cyclic Shifts
Shift rows k times left and right
26.03.2026
hard3548. Equal Sum Grid Partition II
Cut matrix in half sums, can remove one cell
25.03.2026
medium3546. Equal Sum Grid Partition I
Split matrix to equal sums
24.03.2026
medium2906. Construct Product Matrix
Product of other cells in a matrix
23.03.2026
medium1594. Maximum Non Negative Product in a Matrix
Max product path right-down
22.03.2026
easy1886. Determine Whether Matrix Can Be Obtained By Rotation
Rotate matrix
21.03.2026
medium3643. Flip Square Submatrix Vertically
Reverse submatrix k by k
20.03.2026
medium3567. Minimum Absolute Difference in Sliding Submatrix
Mid diffs in k k submatrices
19.03.2026
medium3212. Count Submatrices With Equal Frequency of X and Y
Count prefix freq X == freq Y
18.03.2026
medium3070. Count Submatrices with Top-Left Element and Sum Less Than k
Count prefix sums less than K
17.03.2026
medium1727. Largest Submatrix With Rearrangements
Max area of binary matrix, swap columns
16.03.2026
medium1878. Get Biggest Three Rhombus Sums in a Grid
Top 3 rhombus sums
15.03.2026
hard1622. Fancy Sequence
Design: add number, mulriply all, add all
14.03.2026
medium1415. The k-th Lexicographical String of All Happy Strings of Length n
K-th generated abc non-repeating string
13.03.2026
medium3296. Minimum Number of Seconds to Make Mountain Height Zero
Min steps to work a mountain with arithmetic-sum-workers
12.03.2026
hard3600. Maximize Spanning Tree Stability with Upgrades
Max of min values in span tree of graph, 2 s at most k
11.03.2026
easy1009. Complement of Base 10 Integer
Invert binary
10.03.2026
hard3130. Find All Possible Stable Binary Arrays II
array to make with z zeros, o ones, l repeats
09.03.2026
medium3129. Find All Possible Stable Binary Arrays I
Count 01-arrays with z zeros, o ones, at most l repeat
08.03.2026
medium1980. Find Unique Binary String
Uniq bits not in a set
07.03.2026
medium1888. Minimum Number of Flips to Make the Binary String Alternating
Min flips to make 01 alterating string sum window
06.03.2026
easy1784. Check if Binary String Has at Most One Segment of Ones
+0 pattern
05.03.2026
easy1758. Minimum Changes To Make Alternating Binary String
Min flips to make bits alterating
04.08.2026
easy1582. Special Positions in a Binary Matrix
Count single 1-row-column
03.03.2026
medium1545. Find Kth Bit in Nth Binary String
Kth bit in s=s+1+inv(rev(s)) sequence
02.03.2026
medium1536. Minimum Swaps to Arrange a Binary Grid
Min rows swaps to zero above diagonal
01.03.2026
medium1689. Partitioning Into Minimum Number Of Deci-Binary Numbers
Min 01-strings add up to target
28.02.2026
medium1680. Concatenation of Consecutive Binary Numbers
Concat binaries 1..n
27.02.2026
hard3666. Minimum Operations to Equalize Binary String
Min steps to convert 01 stirng to ones flipping K
26.02.2026
medium1404. Number of Steps to Reduce a Number in Binary Representation to One
Ops /2+1 to make 1
25.02.2026
easy1356. Sort Integers by The Number of 1 Bits
Sort
24.02.2026
easy1022. Sum of Root To Leaf Binary Numbers
Sum of a binary numbers in a binary tree
23.02.2026
medium1461. Check If a String Contains All Binary Codes of Size K
All numbers as substring length of k window
22.02.2026
easy868. Binary Gap
Distance between onces in a binary
21.02.2026
easy762. Prime Number of Set Bits in Binary Representation
Number in l..r with prime bits count
20.02.2026
hard761. Special Binary String
Swaps of 1M0-special substring to make string large
19.02.2026
easy696. Count Binary Substrings
Count substrings of 01 and 10 window
18.02.2026
easy693. Binary Number with Alternating Bits
Alternating bits
17.02.2026
easy401. Binary Watch
All times with count bits set
16.02.2026
easy190. Reverse Bits
Reverse bits
15.02.2026
easy67. Add Binary
Binary strings sum
14.02.2026
medium799. Champagne Tower
Flow in a Pascal's Triangle
13.02.2026
medium3714. Longest Balanced Substring II
Largest equal frequencies substring of abc-string
12.02.2026
medium3713. Longest Balanced Substring I
Max substring with equal frequencies window
11.02.2026
hard3721. Longest Balanced Subarray II
Max subarray evens count = odds count tree
10.02.2026
medium3719. Longest Balanced Subarray I
Longes even=odd subarray
09.02.2026
medium1382. Balance a Binary Search Tree
Balance binary search tree
08.02.2026
easy110. Balanced Binary Tree
Is tree balanced?
07.02.2026
medium1653. Minimum Deletions to Make String Balanced
Min removal to balance 'ab'
06.02.2026
medium3634. Minimum Removals to Balance Array
Min removals to make min k not less than max window
05.02.2026
easy3379. Transformed Array
Shuffled list i+n[i]
03.02.2026
easy3637. Trionic Array I
Validate inc,dec,inc sequency
02.02.2026
hard3013. Divide an Array Into Subarrays With Minimum Cost II
Min sum of k splits at max d distance window
01.02.2026
easy3010. Divide an Array Into Subarrays With Minimum Cost I
Split on 2 min values
31.01.2026
easy744. Find Smallest Letter Greater Than Target
Larger letter in array
30.01.2026
hard2977. Minimum Cost to Convert String II
Min cost to convert string with transitions of substrings
29.01.2026
medium2976. Minimum Cost to Convert String I
Min cost to convert string
28.01.2026
hard3651. Minimum Cost Path with Teleportations
Min cost to walk 2D grid with free teleports
27.01.2026
medium3650. Minimum Cost Path with Edge Reversals
Min path in weighted graph with reverse 2w nodes
26.01.2026
easy1200. Minimum Absolute Difference
Min diff pairs
25.01.2026
easy1984. Minimum Difference Between Highest and Lowest of K Scores
Min k-diff window
24.01.2026
medium1877. Minimize Maximum Pair Sum in Array
Min max pair
23.01.2026
hard3510. Minimum Pair Removal to Sort Array II
Sort by removing min-sum pairs
22.01.2026
easy3507. Minimum Pair Removal to Sort Array I
Sort by removing lowest sum pairs
21.01.2026
medium3315. Construct the Minimum Bitwise Array II
Reverse operation x or (x+1)
20.01.2026
easy3314. Construct the Minimum Bitwise Array I
Reverse x | (x+1) operation on prime numbers
18.01.2026
medium1895. Largest Magic Square
Max magic square
17.01.2026
medium3047. Find the Largest Area of Square Inside Two Rectangles
Max square in intersection
16.01.2026
medium2975. Maximum Square Area by Removing Fences From a Field
Max square after remove vertical or horizontal bars
15.01.2026
medium2943. Maximize Area of Square Hole in Grid
Max square area after removing bars in a grid
14.01.2026
hard3454. Separate Squares II
Min y to equal split areas exclude intersections sweep
13.01.2026
medium3453. Separate Squares I
Min Y to split into equal areas
12.01.2026
easy1266. Minimum Time Visiting All Points
Euclid travel distance
11.01.2026
hard85. Maximal Rectangle
Max all-1 rectangle in 2D matrix stack
10.01.2026
medium712. Minimum ASCII Delete Sum for Two Strings
Min removed sum to make strings equal
09.01.2026
medium865. Smallest Subtree with all the Deepest Nodes
Lowest common ancestor of the deepest nodes
08.01.2026
hard1458. Max Dot Product of Two Subsequences
Max product of 2 subsequencies
07.01.2026
medium1339. Maximum Product of Splitted Binary Tree
Max sumA sumB of a tree split
06.01.2026
medium1161. Maximum Level Sum of a Binary Tree
Min level max sum in tree
05.01.2026
medium1975. Maximum Matrix Sum
Max sum after multiply -1 adjacent cells
03.12.2026
hard1411. Number of Ways to Paint N × 3 Grid
Ways to color 3xN grid
02.01.2026
easy961. N-Repeated Element in Size 2N Array
Duplicate majority element
01.01.2026
easy66. Plus One
Increment big number