C++ practice in Data Structures & Algorithms

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• Even-Channel Filter

  The diagnostics board only counts channels with even IDs. Tally them.

  arrays. Free with an account.

• Peak Reading

  A sensor array reports the hottest cell. Find the maximum reading.

  arrays. Free with an account.

• Telemetry Total

  Mission control needs the total packet count before the downlink window closes.

  arrays. Free with an account.

• Valley Floor

  An altimeter logged the descent. Report the lowest reading in the buffer.

  arrays. Free with an account.

• Access Pair

  Two key cards must sum to the vault code. The card list is sorted; find their slots.

  two-pointers. Free with an account.

• Best Window

  A revenue stream has good days and bad. Find the largest sum any contiguous run of days produces.

  kadane. Free with an account.

• Bracket Integrity

  A config parser rejects malformed nesting. Validate the brackets.

  stack. Free with an account.

• Log Reversal

  The flight recorder writes backward. Reverse the buffer to read it forward.

  two-pointers. Free with an account.

• Find the Target

  A sorted index needs fast lookups. Binary-search for a key and return its position, or -1.

  binary-search. Free with an account.

• Index Locator

  A sorted manifest needs a part looked up fast. Binary search it.

  binary-search. Free with an account.

• Schedule Merge

  Overlapping maintenance windows must be merged before the rollout.

  sorting. Free with an account.

• Top Priority

  The dispatch queue must surface the k-th highest priority job.

  heap. Free with an account.

• Climb the Stairs

  A staircase can be climbed one or two steps at a time. Count the distinct ways to reach the top with dynamic programming.

  dynamic-programming. Free with an account.

• Credit Exchange

  A vending controller must pay an exact amount with the fewest coins, or report failure.

  dp. Free with an account.

• Territory Count

  A drone map marks land as 1 and water as 0. Count the separate landmasses.

  grid, dfs. Free with an account.

• Upgrade Ladder

  A firmware version ladder accepts only strictly increasing picks. Find the longest run.

  dp. Free with an account.

• Common Divisor

  A scheduler aligns two cycle lengths. Compute their greatest common divisor with Euclid's algorithm.

  math. Free with an account.

• Sentinel Placement

  Place n non-attacking sentinels on an n-by-n grid. Count the valid arrangements.

  backtracking. Free with an account.

• Shortest Relay

  A mesh network must report the shortest weighted relay distance from a source to every node.

  dijkstra. Free with an account.

• String Morph

  A protocol upgrader counts the minimum edits to migrate one token to another.

  dp. Free with an account.