| Title | Topics | Action | |||
|---|---|---|---|---|---|
| 185 | Sum a Vector (STL)Write a function int sumVector(const vector<int>& nums) that returns the sum of ... | easy | ○ Not Started | STL Containers | Solve |
| 454 | Insert Into a SetA `set<int>` named `s` has already been declared for you. Insert the values 3, 1... | easy | ○ Not Started | STL ContainersSets | Solve |
| 455 | Print a Set in Sorted OrderA `set<int>` named `s` already holds the values 5, 1 and 3. Write a range-based ... | easy | ○ Not Started | STL ContainersSets | Solve |
| 456 | Duplicates Are IgnoredA `set<int>` named `s` has been declared for you. Insert the values 4, 4, 4 and ... | easy | ○ Not Started | STL ContainersSets | Solve |
| 457 | Check Membership with countWrite a function `bool contains(const set<int>& s, int x)` that returns `true` i... | easy | ○ Not Started | STL ContainersSets | Solve |
| 458 | Erase a Value from a SetA `set<int>` named `s` holds 1, 2, 3 and 4, and a loop that prints the set is al... | easy | ○ Not Started | STL ContainersSets | Solve |
| 459 | Set of Strings Sorts AlphabeticallyA `set<string>` named `names` has been declared, and a loop that prints each nam... | easy | ○ Not Started | STL ContainersSets | Solve |
| 460 | Count Unique ValuesWrite a function `int countUnique(const vector<int>& v)` that returns how many d... | easy | ○ Not Started | STL ContainersSets | Solve |
| 461 | Smallest and Largest in a SetA `set<int>` named `s` holds 7, 2, 9 and 4. Print its smallest value and its lar... | easy | ○ Not Started | STL ContainersSets | Solve |
| 462 | multiset Keeps DuplicatesA `multiset<int>` named `ms` has been declared for you. Insert 3, 3 and 1 (three... | easy | ○ Not Started | STL ContainersSets | Solve |
| 463 | unordered_set LookupWrite a function `bool hasWord(const unordered_set<string>& words, const string&... | easy | ○ Not Started | STL ContainersSets | Solve |
| 478 | Push and Look at the FrontA `queue<int>` named `q` has already been created for you. Push the values 10, 2... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 479 | Pop the FrontA `queue<int>` named `q` already holds 10, 20, 30 (10 is at the front).
Remove ... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 480 | Drain a QueueA `queue<int>` named `q` already holds 1, 2, 3 (1 is at the front).
Write a loo... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 481 | Queue StatusWrite a function `string status(const queue<int>& q)` that returns the string "e... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 482 | Back of the QueueA `queue<int>` named `q` already holds 10, 20, 30 (10 is at the front, 30 is at ... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 483 | Priority Queue Puts Largest on TopA `priority_queue<int>` named `pq` has already been created. Push 5, 1 and 9 (in... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 484 | Min-Heap with greaterA min-heap has already been declared for you: `priority_queue<int, vector<int>, ... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 485 | Serve the Front CustomerWrite a function `void serve(queue<string>& line)` that serves the customer at t... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 486 | Deque Push Both EndsA `deque<int>` named `d` has already been created, and a loop that prints every ... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 487 | Build a Queue from a VectorWrite a function `queue<int> toQueue(const vector<int>& v)` that returns a new `... | easy | ○ Not Started | STL ContainersQueues | Solve |
| 502 | Push and PeekA `stack<int>` named `s` has already been created in main. Push the values 1, 2 ... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 503 | Pop Then PeekA `stack<int>` named `s` already holds 1, 2, 3 (3 is on top). Remove the top ele... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 504 | Drain a StackA `stack<int>` named `s` already holds 1, 2, 3 (3 is on top). Write a loop that ... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 505 | Top or NoneWrite a function `string topOrNone(const stack<int>& s)`. If the stack is empty,... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 506 | Reverse a Word with a StackThe variable `word` holds "hello", and an empty `stack<char>` named `s` and an e... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 507 | Undo History StackA `stack<string>` named `history` already holds three actions pushed in this ord... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 508 | Push All from a VectorWrite a function `void pushAll(stack<int>& s, const vector<int>& v)` that pushes... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 509 | Sum the Top TwoWrite a function `int sumTopTwo(stack<int> s)` that returns the sum of the two e... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 510 | Size After Mixed OperationsAn empty `stack<int>` named `s` is already declared. Perform these six operation... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 511 | Balanced Round BracketsWrite a function `bool balanced(const string& s)` that returns true when every `... | easy | ○ Not Started | STL ContainersStacks | Solve |
| 526 | Fill a std::array in a LoopAn `array<int, 5>` named `a` has already been declared for you, and two loops ar... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 527 | Size of a std::arrayAn `array<int, 4>` named `a` has been created with the values {10, 20, 30, 40}. ... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 528 | Sum a std::arrayWrite a function `int sumArray(const array<int, 5>& a)` that returns the sum of ... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 529 | fill With One ValueAn array `a` of four ints has been declared but not initialized, and a printing ... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 530 | front and backAn `array<int, 3>` named `a` has been created with the values {3, 5, 9}.
Print ... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 531 | Bounds-Checked at()An `array<int, 4>` named `a` holds {1, 2, 3, 4} and an `int index` is set to 10.... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 532 | Largest in a std::arrayWrite a function `int maxOf(const array<int, 6>& a)` that returns the largest of... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 533 | Array of Strings With IndexAn `array<string, 3>` named `days` has been created with the values {"Mon", "Tue... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 534 | Copying a std::arrayThe code already creates `array<int, 3> a = {1, 2, 3};`, copies it with `array<i... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 535 | Sort a std::arrayAn `array<int, 4>` named `a` holds {5, 1, 8, 2}, and a printing loop is already ... | easy | ○ Not Started | STL Containersstd::array | Solve |
| 550 | Print with an Iterator LoopA vector `v` has already been created with the values {1, 2, 3}. Write a for loo... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 551 | Dereference and AdvanceA vector `v` has already been created with the values {10, 20, 30}. Complete the... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 552 | Reverse IterationA vector `v` has already been created with the values {1, 2, 3}. Write a loop fr... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 553 | Modify Through an IteratorA vector `v` has already been created with the values {1, 2, 3}, and an iterator... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 554 | const_iterator SumWrite a function `int sumConst(const vector<int>& v)` that adds up every element... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 555 | Distance Between IteratorsA vector `v` has already been created with the values {5, 6, 7, 8}. Use `std::di... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 556 | find Returns an IteratorA vector `v` has already been created with the values {10, 20, 30, 40} and an in... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 557 | next and prevA vector `v` has already been created with the values {1, 2, 3, 4, 5}. Complete ... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 558 | Erase via IteratorA vector `v` has already been created with the values {1, 2, 3, 4}. Erase the el... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 559 | Iterating a std::setA set `s` has already been created from the values {6, 2, 4}. Write an iterator ... | easy | ○ Not Started | STL ContainersIterators | Solve |
| 186 | Sort a Vector with std::sortUse std::sort to sort a vector of ints in ascending order. Write a function void... | medium | ○ Not Started | STL Containers | Solve |
| 187 | Count Occurrences with std::mapWrite a function int countOccurrences(const vector<int>& nums, int target) that ... | medium | ○ Not Started | STL Containers | Solve |
| 464 | Unique Numbers from InputWrite a program that reads an integer N from standard input followed by N intege... | medium | ○ Not Started | STL ContainersSets | Solve |
| 465 | Count Newly Inserted ValuesWrite a function `int insertAll(set<int>& s, const vector<int>& v)` that inserts... | medium | ○ Not Started | STL ContainersSets | Solve |
| 466 | Common Elements of Two SetsWrite a function `vector<int> commonElements(const set<int>& a, const set<int>& ... | medium | ○ Not Started | STL ContainersSets | Solve |
| 467 | Elements Only in the First SetWrite a function `set<int> difference(const set<int>& a, const set<int>& b)` tha... | medium | ○ Not Started | STL ContainersSets | Solve |
| 468 | Remove Duplicate WordsWrite a program that reads words from standard input until the input ends (use `... | medium | ○ Not Started | STL ContainersSets | Solve |
| 469 | Erase Evens While IteratingWrite a function `void removeEvens(set<int>& s)` that erases every even value fr... | medium | ○ Not Started | STL ContainersSets | Solve |
| 470 | First Repeated NumberKeep a `set<int>` of the values seen so far.
Write a function `int firstRepeat(... | medium | ○ Not Started | STL ContainersSets | Solve |
| 471 | First Value At Least XWrite a function `int firstAtLeast(const set<int>& s, int x)` that returns the s... | medium | ○ Not Started | STL ContainersSets | Solve |
| 472 | Tally a multisetA `multiset<int>` named `ms` already holds the values 2, 5, 2, 8, 5, 2. Print ea... | medium | ○ Not Started | STL ContainersSets | Solve |
| 473 | Are All Elements Unique?Write a function `bool allUnique(const vector<int>& v)` that returns `true` if n... | medium | ○ Not Started | STL ContainersSets | Solve |
| 488 | Read Numbers Into a QueueWrite a program that reads an integer N from standard input, followed by N integ... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 489 | Sum a Queue Without Emptying ItWrite a function `int sumQueue(queue<int> q)` that returns the sum of every elem... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 490 | Ticket Line SimulationSimulate a ticket line with a `queue<string>`. Read commands from standard input... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 491 | Top K LargestWrite a function `vector<int> topK(const vector<int>& v, int k)` that returns th... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 492 | Reverse a Queue Using a StackWrite a function `void reverseQueue(queue<int>& q)` that reverses the order of t... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 493 | Print Heap Values DescendingA `priority_queue<int>` named `pq` has already been created and filled with 4, 9... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 494 | Priority Queue of PairsA `priority_queue<pair<int, string>> tasks;` has already been declared. Each pai... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 495 | Interleave Two QueuesWrite a function `queue<int> interleave(queue<int> a, queue<int> b)` that return... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 496 | Keep Only the Last NWrite a function `deque<int> keepLast(const vector<int>& v, int n)` that returns... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 497 | Kth Smallest with a Min-HeapWrite a function `int kthSmallest(const vector<int>& v, int k)` that returns the... | medium | ○ Not Started | STL ContainersQueues | Solve |
| 512 | Reverse Numbers from InputWrite a program that reads integers from standard input until the input ends, pu... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 513 | Balanced Brackets Three KindsWrite a function `bool isBalanced(const string& s)` that uses a `stack<char>` to... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 514 | Evaluate PostfixWrite a function `int evalPostfix(const vector<string>& tokens)` that uses a `st... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 515 | Decimal to Binary with a StackWrite a function `string toBinary(int n)` that returns the binary representation... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 516 | Sum a Stack CopyWrite a function `int sumStack(stack<int> s)` that returns the sum of every elem... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 517 | Undo Text EditorWrite a program that simulates a tiny text editor with undo. Read commands from ... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 518 | Next Greater ElementWrite a function `vector<int> nextGreater(const vector<int>& v)` that returns a ... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 519 | Stack to Vector Bottom FirstWrite a function `vector<int> bottomFirst(stack<int> s)` that returns the stack'... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 520 | Remove Adjacent DuplicatesWrite a function `string removeAdjacent(const string& s)` that uses a `stack<cha... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 521 | Palindrome Check with a StackWrite a function `bool isPalindrome(const string& s)` that uses a `stack<char>` ... | medium | ○ Not Started | STL ContainersStacks | Solve |
| 536 | Five Numbers from InputWrite a program that reads exactly five integers from standard input (separated ... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 537 | Reverse a std::array In PlaceWrite a function `void reverseArray(array<int, 5>& a)` that reverses the order o... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 538 | Count Even ValuesWrite a function `int countEven(const array<int, 8>& a)` that returns how many o... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 539 | Sum Any Size (Template Parameter)Write a function template `template <size_t N> int sumAny(const array<int, N>& a... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 540 | 3x3 Grid with Nested std::arrayA variable `grid` of type `array<array<int, 3>, 3>` has been declared for you.
... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 541 | Index of a ValueWrite a function `int indexOf(const array<int, 6>& a, int x)` that returns the i... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 542 | Rotate Left by OneWrite a function `void rotateLeft(array<int, 5>& a)` that moves every element on... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 543 | Swap Two ArraysThe code already creates `array<int, 3> a = {1, 2, 3};` and `array<int, 3> b = {... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 544 | Weekly Temperature ReportAn `array<double, 7>` named `temps` holds one temperature per day of the week: {... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 545 | Compare Two ArraysWrite a function `bool sameContents(const array<int, 4>& a, const array<int, 4>&... | medium | ○ Not Started | STL Containersstd::array | Solve |
| 560 | Sum Between Two IteratorsWrite a function `int sumRange(vector<int>::iterator first, vector<int>::iterato... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 561 | Erase Every Matching ValueWrite a function `void removeValue(vector<int>& v, int x)` that removes every el... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 562 | Insert Before a ValueWrite a function `void insertBefore(vector<int>& v, int target, int val)` that:
... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 563 | Second Largest with Iterator ArithmeticWrite a function `int secondLargest(vector<int> v)` that returns the second-larg... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 564 | Print Every Other ElementWrite a function `void printEveryOther(const vector<int>& v)` that prints the el... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 565 | Reverse a String with Reverse IteratorsWrite a function `string reversed(const string& s)` that returns a new string co... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 566 | Index of the MaximumWrite a function `int indexOfMax(const vector<int>& v)` that returns the 0-based... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 567 | Iterate a Map with IteratorsA `map<string, int>` named `stock` has already been created with `apple` mapped ... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 568 | Reverse Input with Reverse IteratorsWrite a program that reads whole numbers from standard input until there is no m... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 569 | First Half by Iterator RangeWrite a function `vector<int> firstHalf(const vector<int>& v)` that returns a ne... | medium | ○ Not Started | STL ContainersIterators | Solve |
| 474 | Unique Word TrackerBuild a class `UniqueWords` that stores the distinct words in a `set<string>`. I... | hard | ○ Not Started | STL ContainersSets | Solve |
| 475 | Number Set Range QueriesBuild a class `NumberSet` that stores distinct integers in a `set<int>` and answ... | hard | ○ Not Started | STL ContainersSets | Solve |
| 476 | Set Algebra From InputRead two lines from standard input. The first line holds the integers of set A a... | hard | ○ Not Started | STL ContainersSets | Solve |
| 477 | Inventory with multisetBuild a class `Inventory` that stores item names in a `multiset<string>`, so the... | hard | ○ Not Started | STL ContainersSets | Solve |
| 498 | Printer Job SchedulerBuild a class `PrintQueue` that serves print jobs first-come, first-served, stor... | hard | ○ Not Started | STL ContainersQueues | Solve |
| 499 | Emergency Room TriageBuild a class `Triage` that decides which emergency-room patient is seen next, u... | hard | ○ Not Started | STL ContainersQueues | Solve |
| 500 | Round-Robin SchedulerWrite a round-robin CPU scheduler. Input: the first line holds the time quantum ... | hard | ○ Not Started | STL ContainersQueues | Solve |
| 501 | Josephus Elimination Ordern people numbered 1 to n stand in a circle. Counting from person 1, every k-th p... | hard | ○ Not Started | STL ContainersQueues | Solve |
| 522 | Min StackBuild a class `MinStack` that behaves like a normal stack of ints but can also r... | hard | ○ Not Started | STL ContainersStacks | Solve |
| 523 | Infix to PostfixWrite a function `string toPostfix(const string& expr)` that converts an infix a... | hard | ○ Not Started | STL ContainersStacks | Solve |
| 524 | Browser HistoryBuild a class `BrowserHistory` that models the back and forward buttons of a web... | hard | ○ Not Started | STL ContainersStacks | Solve |
| 525 | Queue Made of Two StacksBuild a class `StackQueue` that behaves like a first-in first-out queue of ints ... | hard | ○ Not Started | STL ContainersStacks | Solve |
| 546 | Fixed-Size Ring BufferBuild a class `RingBuffer` that stores its values in an `array<int, 4>` (capacit... | hard | ○ Not Started | STL Containersstd::array | Solve |
| 547 | Tic-Tac-Toe WinnerA tic-tac-toe board is an `array<array<char, 3>, 3>`: `b[row][col]` is `'X'`, `'... | hard | ○ Not Started | STL Containersstd::array | Solve |
| 548 | 2x2 Matrix MultiplyA 2x2 matrix is an `array<array<int, 2>, 2>`, where `m[r][c]` is the value in ro... | hard | ○ Not Started | STL Containersstd::array | Solve |
| 549 | Digit Histogram from InputWrite a program that reads non-negative integers from standard input until the i... | hard | ○ Not Started | STL Containersstd::array | Solve |
| 570 | Countdown Range ClassCreate a class `Countdown` with:
1. A constructor `Countdown(int n)` that stores... | hard | ○ Not Started | STL ContainersIterators | Solve |
| 571 | Remove Duplicates Keeping OrderWrite a function `void dedupe(vector<int>& v)` that modifies `v` in place so tha... | hard | ○ Not Started | STL ContainersIterators | Solve |
| 572 | Merge Two Sorted VectorsWrite a function `vector<int> mergeSorted(const vector<int>& a, const vector<int... | hard | ○ Not Started | STL ContainersIterators | Solve |
| 573 | Linked List with IteratorCreate a class `IntList`, a singly linked list of ints, with:
1. A private neste... | hard | ○ Not Started | STL ContainersIterators | Solve |