Pattern

Two Pointers

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64 entries

64 entries tagged as Two Pointers.

06.11.2026

medium

2747. Count Zero Request Servers

Kotlin Rust

Queries: servers without requests in range t-x..t

Two Pointers Sorting

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26.08.2026

medium

2904. Shortest and Lexicographically Smallest Beautiful String

Kotlin Rust

Smallest substring with k-ones

Two Pointers Simulation String

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19.05.2026

easy

2540. Minimum Common Value

Kotlin Rust

Min common of two sorted list

Binary Search Two Pointers

array hash set binary search two pointers merge sorted lists arrays

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04.10.2025

medium

11. Container With Most Water

Kotlin Rust

Max water container from two heights

Two Pointers

heights max_area container_with_most_water

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24.08.2025

medium

1493. Longest Subarray of 1's After Deleting One Element

Kotlin Rust

Max 1-subarray after removing one elemnt pointers

Two Pointers

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29.07.2025

medium

2411. Smallest Subarrays With Maximum Bitwise OR

Kotlin Rust

Shortest max OR i.. subarrays pointers

Two Pointers Bit Manipulation

n backward_expansion backward_pass forward_pass n bit_frequency_tracking

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30.06.2025

easy

594. Longest Harmonious Subsequence

Kotlin Rust

Longest subsequence with max-min=1 pointers

Two Pointers Sorting

sorting two-pointers arrays counting

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29.06.2025

medium

1498. Number of Subsequences That Satisfy the Given Sum Condition

Kotlin Rust

Subsequencies target in 0..min+max search pointers

Binary Search Two Pointers Sorting

n f sort bs two-pointers dp

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17.05.2025

medium

75. Sort Colors

Kotlin Rust

Sort 0,1,2 array pointers

Two Pointers Sorting Array

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29.04.2025

medium

2962. Count Subarrays Where Max Element Appears at Least K Times

Kotlin Rust

Subarrays at least k maxes pointers

Two Pointers

n q two_pointers sliding_window two_pointers n

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28.04.2025

hard

2302. Count Subarrays With Score Less Than K

Kotlin Rust

Subarrays sum cnt <= k pointers

Two Pointers

none two-pointers sliding-window arrays

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26.04.2025

hard

2444. Count Subarrays With Fixed Bounds

Kotlin Rust

Subarrays with min=minK, max=maxK pointers

Two Pointers

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24.04.2025

medium

2799. Count Complete Subarrays in an Array

Kotlin Rust

Subarrays having all uniqs pointers

Two Pointers Array

frequency_array sliding_window frequency_counting_and_tracking two_pointer_state_management array_manipulation

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19.04.2025

medium

2563. Count the Number of Fair Pairs

Kotlin Rust

Pairs a + b in lower..upper pointers

Two Pointers

arrays two-pointers sorting arrays

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18.03.2025

medium

2401. Longest Nice Subarray

Kotlin Rust

Max window of all pairs AND zero pointers manipulation

Bit Manipulation Two Pointers Hash Map

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11.03.2025

medium

1358. Number of Substrings Containing All Three Characters

Kotlin Rust

Substrings with [abc] pointers

Two Pointers

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10.03.2025

medium

3306. Count of Substrings Containing Every Vowel and K Consonants II

Kotlin Rust

Substring with all vowels and k others pointers

Two Pointers String

array string two-pointers at_least_difference indexOf_trick strings

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09.03.2025

medium

3208. Alternating Groups II

Kotlin Rust

Count cycling alterating k-subarrays pointers

Two Pointers

two-pointers xor arrays

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03.03.2025

medium

2161. Partition Array According to Given Pivot

Kotlin Rust

Partition around p

Two Pointers Array

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02.03.2025

easy

2570. Merge Two 2D Arrays by Summing Values

Kotlin Rust

Merge two ascending [key, value] lists

Two Pointers Sorting Array

hash-map bmap vec sort pointers summation-by-key

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14.12.2024

medium

2762. Continuous Subarrays

Kotlin Rust

Count subarrays with difference <= 2 queue set

Tree Two Pointers Sliding Window

TreeSet MonotonicQueue VecDeque Multiset SlidingWindow Arrays

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09.12.2024

medium

3152. Special Array II

Kotlin Rust

Queries is all adjucents parity differ [i..j] pointers

Two Pointers Array

Two Pointers for range queries and island identification Enumerating islands to assign unique keys Array manipulation and range queries

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06.12.2024

medium

2554. Maximum Number of Integers to Choose From a Range I

Kotlin Rust

Sum 1..n excluding banned until maxSum

Binary Search Two Pointers Sorting

HashSet Array Sorting Two Pointers Prefix Sum Set Lookup

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20.11.2024

medium

2516. Take K of Each Character From Left and Right

Kotlin Rust

Min take k of a,b,c from head or tail pointers

Two Pointers Sliding Window

prefix-sum sliding-window prefix-sum-sliding-window frequency-array-sliding-window string-manipulation

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19.11.2024

medium

2461. Maximum Sum of Distinct Subarrays With Length K

Kotlin Rust

Max k-unique window sum window

Two Pointers Sliding Window

HashSet Sliding Window Sliding Window with Hash Set Arrays

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15.11.2024

medium

1574. Shortest Subarray to be Removed to Make Array Sorted

Kotlin Rust

Min subarray remove to make array sorted pointers

Two Pointers Array

array vector two-pointers arrays strings

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13.11.2024

medium

2563. Count the Number of Fair Pairs

Kotlin Rust

Count pairs a[i] + a[j] in lower..upper search pointers

Binary Search Two Pointers

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04.11.2024

medium

3163. String Compression III

Kotlin Rust

Compress repeating chars in string pointers

Two Pointers Hash Map String

string array two-pointers string-compression strings

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01.11.2024

easy

1957. Delete Characters to Make Fancy String

Kotlin Rust

Filter 3+ repeating chars from string

Two Pointers Hash Map String

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08.10.2024

medium

1963. Minimum Number of Swaps to Make the String Balanced

Kotlin Rust

Min swaps to balance brackets pointers

Stack Two Pointers String

Two pointers approach for identifying misplaced brackets. Implicit use of a stack concept via balance tracking to manage bracket nesting. String manipulation and bracket balancing. Linear scan over the input string.

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05.10.2024

medium

567. Permutation in String

Kotlin Rust

Is s2 contains permutation of s1? pointers

Two Pointers String

frequency array/count array implicit frequency counting via array index sliding window/frequency comparison using frequency arrays to check permutation existence implicit sliding window logic via frequency adjustments permutation checking on strings

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04.10.2024

medium

2491. Divide Players Into Teams of Equal Skill

Kotlin Rust

Sum of products of pairs with equal sums

Math Two Pointers Sorting

IntArray HashMap Greedy Frequency Counting Two Pointers Math

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28.09.2024

medium

641. Design Circular Deque

Kotlin Rust

Ring buffer

Two Pointers Queue Array

array linked-list pointer-arithmetic data-structures arrays

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15.09.2024

medium

1371. Find the Longest Substring Containing Vowels in Even Counts

Kotlin Rust

Longest substring with even number of "aeiou" manipulation pointers

Bit Manipulation Two Pointers String

HashMap Two Pointers Bit Manipulation Strings

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14.09.2024

medium

2419. Longest Subarray With Maximum Bitwise AND

Kotlin Rust

Max bitwise AND subarray manipulation pointers

Bit Manipulation Two Pointers

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14.08.2024

hard

719. Find K-th Smallest Pair Distance

Kotlin Rust

kth smallest pairs diff in an array search pointers

Binary Search Two Pointers Array

nums k binary_search two_pointers nums

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04.08.2024

medium

1508. Range Sum of Sorted Subarray Sums

Kotlin Rust

Sum of [left..right] of sorted subarray's sums

Heap Binary Search Two Pointers

heap array priority-queue search prefix-sum heap-based-sliding-window

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2.07.2024

easy

350. Intersection of Two Arrays II

Kotlin Rust

Array intersection with duplicates

Two Pointers Sorting Array

counting sort sorting sorting sorting in-place modification array manipulation

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08.06.2024

medium

523. Continuous Subarray Sum

Kotlin Rust

Any subarray sum % k = 0

Hash Map Two Pointers Array

hash-map hash-set prefix-sum modulo-invariant arrays strings

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02.06.2024

easy

344. Reverse String

Kotlin Rust

Reverse an array

Two Pointers String Array

array vector in-place reversal built-in function usage strings arrays

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04.05.2024

medium

881. Boats to Save People

Kotlin Rust

Minimum total boats with at most 2 people & limit weight pointers

Greedy Two Pointers

people array used for sorting and iteration sorting the people array in descending order using two pointers (i and j) to pair people sorting descending and pairing the heaviest remaining person with the lightest possible person handling an array of people weights

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03.05.2024

medium

165. Compare Version Numbers

Kotlin Rust

Compare version numbers

Two Pointers

list vector none split zip strings

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02.05.2024

easy

2441. Largest Positive Integer That Exists With Its Negative

Kotlin Rust

Max number that has its negative in array pointers

Two Pointers Sorting Array

nums counts sort two_pointers nums

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30.04.2024

medium

1915. Number of Wonderful Substrings

Kotlin Rust

Count substrings with at most one odd frequency manipulation

Bit Manipulation Dynamic Programming Two Pointers

array hash_map bit_manipulation prefix_xor_masks bitmask_counting strings

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27.03.2024

medium

713. Subarray Product Less Than K

Kotlin Rust

Subarrays count with product less than k

Two Pointers

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21.03.2024

easy

206. Reverse Linked List

Kotlin Rust

Reverse a Linked List

Two Pointers Linked List

linked-list recursion recursive reversal

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09.03.2024

easy

2540. Minimum Common Value

Kotlin Rust

First common number in two sorted arrays

Two Pointers

hash-set two-pointers set-lookup two-pointer-search arrays

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06.03.2024

easy

141. Linked List Cycle

Kotlin

Detect cycle

Two Pointers Linked List

linked-list recursion two-pointers fast-slow-pointer

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02.03.2024

easy

977. Squares of a Sorted Array

Kotlin Rust

Sorted squares.

Two Pointers Array

array two-pointers two-pointers absolute-value comparison arrays

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14.02.2024

medium

2149. Rearrange Array Elements by Sign

Kotlin Rust

Rearrange array to positive-negative sequence.

Two Pointers Array

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1.01.2024

easy

455. Assign Cookies

Kotlin

Max count of greedy children g[Int] to assign cookies with sizes s[Int].

Two Pointers Greedy Sorting

PriorityQueue Array Sorting Two Pointers Greedy Sorting and Two Pointers

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1.10.2023

easy

557. Reverse Words in a String III

Kotlin

Reverse words

Two Pointers String

strings

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23.09.2023

medium

1048. Longest String Chain

Kotlin

Longest chain of words with single character added

Graph Two Pointers String

mutableMapOf mutableSetOf dfs graph construction dfs string manipulation

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22.09.2023

easy

392. Is Subsequence

Kotlin

Is string a subsequence of another

Trie Two Pointers String

string comparison and subsequence check

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25.08.2023

medium

97. Interleaving String

Kotlin

Can a string be a merge of two other strings

Graph Two Pointers String

mutable map implicit recursion via dfs depth-first search memoization/caching state caching via map recursive exploration of choices

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6.07.2023

medium

209. Minimum Size Subarray Sum

Kotlin

Min length subarray with sum >= target

Two Pointers

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5.07.2023

medium

1493. Longest Subarray of 1's After Deleting One Element

Kotlin

Largest 1..1 subarray after removing one item

Two Pointers Array

arrays

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27.06.2023

medium

373. Find K Pairs with Smallest Sums

Kotlin

List of increasing sum pairs a[i], b[j] from two sorted lists a, b

Graph Backtracking Two Pointers

heap set dijkstra visited-set pairs sorting

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26.06.2023

medium

2462. Total Cost to Hire K Workers

Kotlin

The sum of the smallest cost from suffix and prefix of a costs size of candidates in k iterations

Two Pointers Queue Array

priority-queue two-pointers priority-queue-selection array optimization

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05.04.2023

medium

2439. Minimize Maximum of Array

Kotlin

careful with integers overflows

Binary Search Two Pointers Array

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03.04.2023

medium

881. Boats to Save People

Kotlin

Sort an array and move two pointers lo and hi.

Two Pointers Sorting Array

people sort two-pointers people boats_to_save_people

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09.03.2023

medium

142. Linked List Cycle II

Kotlin

careful with corner cases.

Two Pointers Linked List

linked-list two-pointer slow-fast cycle-detection meeting-point-finding

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6.02.2023

easy

1470. Shuffle the Array

Kotlin

For simplicity, use two pointers for the source, and one for the destination.

Two Pointers Array

array two-pointers two-pointer arrays

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4.11.2022

easy

Reverse Vowels Of A String

Kotlin

Straightforward solution : use two pointers method and scan from the both sides.

Two Pointers String

char_array two-pointers two-pointer vowel swap strings

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