AceStack AI Open interactive practice

Public task directory

Technical interview practice tasks

Every entry below is a crawlable link to a unique public task page. This directory complements the interactive filters and keeps the complete catalog connected through standard pagination.

Page 2 of 386 · 18,491 tasks

Coding (Algo) · Easy · 25 min

Count Allowed Jumps

Algorithm: Dynamic programming Difficulty: Easy Time: 25 minutes Goal Return the exact number of valid one-or-two-step jump sequences from position 0 to n.

Coding (Algo) · Medium · 35 min

Count Clear Routes

Algorithm: Dynamic programming Difficulty: Medium Time: 35 minutes Goal Return the number of clear right-and-down routes from the top-left cell to the bottom-right cell.

Coding (Algo) · Medium · 40 min

Count Valid Parenthesis Structures

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Count distinct balanced parenthesis strings containing exactly n opening and n closing parentheses.

Coding (Algo) · Medium · 40 min

Count Ways to Make an Exact Amount

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Count unordered combinations of the distinct denominations that sum exactly to the requested amount.

Coding (Algo) · Medium · 40 min

Find the Cheapest Monotone Route

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Return the smallest possible sum of visited cell costs for a valid right-or-down route.

Coding (Algo) · Medium · 40 min

Find the Strongest Continuous Period

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Return the greatest sum of any non-empty contiguous segment of the supplied changes.

Coding (Algo) · Medium · 40 min

Locate the Strongest Continuous Period

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Return inclusive start and end indexes of a maximum-sum non-empty contiguous segment using the declared tie rule.

Coding (Algo) · Medium · 40 min

Measure the Shared Ordered Sequence

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Return the length of the longest common subsequence while preserving relative order in both strings.

Coding (Algo) · Hard · 60 min

Minimal Sync Deletions

Algorithm: Dynamic programming Difficulty: Hard Time: 60 minutes Goal Return the minimum total number of deletions needed to make the histories identical.

Coding (Algo) · Hard · 60 min

Minimum Capability Bundle

Algorithm: Dynamic programming Difficulty: Hard Time: 60 minutes Goal Return the cheapest set of packages covering all required capabilities.

Coding (Algo) · Medium · 40 min

Minimum Text Edits

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Return the minimum number of allowed edits needed to turn a into b. Each edit costs one.

Coding (Algo) · Medium · 35 min

Minimum Token Payment

Algorithm: Dynamic programming Difficulty: Medium Time: 35 minutes Goal Return the fewest tokens whose values sum exactly to amount, or -1 when no combination reaches it.

Coding (Algo) · Hard · 75 min

Offline Download Plan

Algorithm: Dynamic programming Difficulty: Hard Time: 75 minutes Goal Return the best package selection, minimizing used capacity on value ties and choosing the lexicographically smallest.

Coding (Algo) · Hard · 75 min

Shortest Shared Replay

Algorithm: Dynamic programming Difficulty: Hard Time: 75 minutes Goal Return the lexicographically smallest shortest common supersequence.

Coding (Algo) · Medium · 40 min

Split a Batch Into Equal Totals

Algorithm: Dynamic programming Difficulty: Medium Time: 40 minutes Goal Return whether all entries can be partitioned into two subsets with exactly equal sums.

Coding (Algo) · Medium · 35 min

Split Text Into Known Tokens

Algorithm: Dynamic programming Difficulty: Medium Time: 35 minutes Goal Return whether the entire text can be segmented into one or more dictionary words with no skipped or reordered.

Coding (Algo) · Hard · 60 min

Wildcard Route Match

Algorithm: Dynamic programming Difficulty: Hard Time: 60 minutes Goal Match the entire path using ? for one character and for zero or more characters.

Coding (Algo) · Easy · 20 min

Expired Cache Keys

Algorithm: Expiry Difficulty: Easy Time: 20 minutes Goal Return expired keys in input order.

Coding (Algo) · Easy · 20 min

Healthy Instance IDs

Algorithm: Filtering Difficulty: Easy Time: 20 minutes Goal Return eligible IDs in ascending ASCII order.

Coding (Algo) · Easy · 20 min

Recorded Route Distance

Algorithm: Geometry Difficulty: Easy Time: 20 minutes Goal Sum distances between adjacent recorded points.

Coding (Algo) · Medium · 35 min

Count Connected Groups

Algorithm: Graph traversal Difficulty: Medium Time: 35 minutes Goal Return how many connected components exist among all n devices after considering every edge.

Coding (Algo) · Easy · 25 min

Count Reachable Services

Algorithm: Graph traversal Difficulty: Easy Time: 25 minutes Goal Count the distinct nodes reachable from source by following zero or more directed edges and ignoring repeated visits.

Coding (Algo) · Medium · 40 min

Measure Disconnected Groups

Algorithm: Graph traversal Difficulty: Medium Time: 40 minutes Goal Return the sizes of all weakly connected components in descending numeric order while counting each declared node exactly.

Coding (Algo) · Medium · 35 min

Split Conflicting Services

Algorithm: Graph traversal Difficulty: Medium Time: 35 minutes Goal Return whether all n services can be assigned to two groups while satisfying every conflict edge.

Coding (Algo) · Medium · 30 min

Choose Compatible Time Windows

Algorithm: Greedy Difficulty: Medium Time: 30 minutes Goal Return the largest number of pairwise non-overlapping retained requests under the supplied endpoint rule.

Coding (Algo) · Medium · 30 min

Count Connected Window Groups

Algorithm: Greedy Difficulty: Medium Time: 30 minutes Goal Return the number of connected groups formed by overlap among the retained intervals.

Coding (Algo) · Medium · 30 min

Measure Concurrent Reservations

Algorithm: Greedy Difficulty: Medium Time: 30 minutes Goal Return the maximum number of retained reservations active at the same real-valued time.

Coding (Algo) · Medium · 30 min

Measure Total Covered Time

Algorithm: Greedy Difficulty: Medium Time: 30 minutes Goal Return the numeric length of the union of all retained intervals without counting any covered segment more than once.

Coding (Algo) · Medium · 35 min

Minimum Coverage Checkpoints

Algorithm: Greedy Difficulty: Medium Time: 35 minutes Goal Return the minimum number of checkpoints needed to hit every closed interval at least once.

Coding (Algo) · Medium · 30 min

Place the Fewest Inspection Points

Algorithm: Greedy Difficulty: Medium Time: 30 minutes Goal Return the minimum number of real-valued points required to intersect every retained interval.

Coding (Algo) · Easy · 25 min

Account Ledger Totals

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Sum adjustments per account and return accounts in ASCII order.

Coding (Algo) · Medium · 40 min

Count Matching Measurement Gaps

Algorithm: Hash map Difficulty: Medium Time: 40 minutes Goal Count index pairs i < j whose values have exactly the requested absolute difference.

Coding (Algo) · Easy · 25 min

Count Matching Pairs

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Return the number of index pairs i < j for which nums[i] + nums[j] equals target.

Coding (Algo) · Easy · 25 min

Count Repeated Event Types

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Return the number of distinct event values whose total frequency is at least k.

Coding (Algo) · Easy · 25 min

Duration Buckets

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Return only occupied buckets sorted by bucket number.

Coding (Algo) · Easy · 20 min

Find a Pair With the Target Total

Algorithm: Hash map Difficulty: Easy Time: 20 minutes Goal Return whether two different indexes in the supplied amount array have values that sum exactly to the target.

Coding (Algo) · Easy · 25 min

Find the First Unrepeated Event

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Return the first event value that occurs exactly once across the complete input stream.

Coding (Algo) · Medium · 30 min

Idempotency Acceptance Trace

Algorithm: Hash map Difficulty: Medium Time: 30 minutes Goal Return whether each time-ordered request is accepted.

Coding (Algo) · Easy · 25 min

Latest Notification Payload

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Deduplicate by ID using the last payload and the first occurrence order.

Coding (Algo) · Medium · 45 min

LRU Cache Trace

Algorithm: Hash map Difficulty: Medium Time: 45 minutes Goal Simulate get and put operations and return get results.

Coding (Algo) · Medium · 35 min

Rank Frequent Values

Algorithm: Hash map Difficulty: Medium Time: 35 minutes Goal Return the k most frequent distinct values ordered by descending count and then ascending numeric value.

Coding (Algo) · Hard · 45 min

Replay Cache Operations

Algorithm: Hash map Difficulty: Hard Time: 45 minutes Goal Process the operations in order and return each get result while enforcing cache capacity and recency on reads and writes.

Coding (Algo) · Easy · 20 min

Selected Cart Total

Algorithm: Hash map Difficulty: Easy Time: 20 minutes Goal Return the selected total in integer cents without charging for an ID more than once.

Coding (Algo) · Easy · 25 min

Summarize Event Frequencies

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Return one value and count pair for every distinct event code in ascending numeric order.

Coding (Algo) · Medium · 30 min

Top Requested Routes

Algorithm: Hash map Difficulty: Medium Time: 30 minutes Goal Return at most k route names sorted by decreasing frequency then ascending ASCII name.

Coding (Algo) · Easy · 25 min

Unread Thread Badges

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Return unread counts for threads with at least one unread message in ascending ASCII order.

Coding (Algo) · Easy · 25 min

Visible Tag Counts

Algorithm: Hash map Difficulty: Easy Time: 25 minutes Goal Count case-sensitive tags without changing first-appearance ordering.

Coding (Algo) · Easy · 20 min

First Replayed Request

Algorithm: Hash set Difficulty: Easy Time: 20 minutes Goal Return the index of the earliest duplicate occurrence.