migrate 392 questions to pattern format

backend/data/patterns/patterns.yaml

@@ -177,3 +177,83 @@ patterns:
       - Flood fill
       - Rotting oranges
       - Word search in grid
+
+  - name: Topological Sort
+    slug: topological-sort
+    description: Order vertices in a directed acyclic graph (DAG) such that for every edge u→v, u comes before v.
+    when_to_use: |
+      - Course scheduling with prerequisites
+      - Build order / dependency resolution
+      - Task scheduling with dependencies
+      - Alien dictionary problems
+      - Detecting cycles in directed graphs
+
+  - name: Bit Manipulation
+    slug: bit-manipulation
+    description: Use bitwise operations (AND, OR, XOR, shifts) to solve problems efficiently.
+    when_to_use: |
+      - Finding single/missing numbers (XOR tricks)
+      - Counting set bits
+      - Power of two checks
+      - Subset generation with bitmasks
+      - Swapping without temp variable
+
+  - name: Counting / Bucket Sort
+    slug: counting-sort
+    description: Sort or process elements by using their values as indices when the range is bounded.
+    when_to_use: |
+      - Top K frequent elements (bounded frequency range)
+      - Sort Colors (Dutch National Flag)
+      - H-Index calculation
+      - Problems where values are in known small range
+      - Frequency-based grouping
+
+  - name: Cyclic Sort
+    slug: cyclic-sort
+    description: Place each element at its correct index when values are in range [1, n] or [0, n-1].
+    when_to_use: |
+      - Find missing number in [1, n]
+      - Find duplicate in [1, n]
+      - Find all missing/duplicate numbers
+      - First missing positive
+      - Set mismatch problems
+
+  - name: Divide and Conquer
+    slug: divide-and-conquer
+    description: Split problem into smaller subproblems, solve recursively, and combine results.
+    when_to_use: |
+      - Merge sort and related problems
+      - Quick select for kth element
+      - Binary search variants
+      - Matrix multiplication
+      - Closest pair of points
+
+  - name: Hashing
+    slug: hashing
+    description: Use hash tables for O(1) average lookup, insertion, and deletion.
+    when_to_use: |
+      - Two Sum and variants
+      - Detecting duplicates
+      - Frequency counting
+      - Anagram grouping
+      - LRU/LFU cache implementation
+
+  - name: Matrix Manipulation
+    slug: matrix-manipulation
+    description: Transform or process 2D matrices using rotation, transposition, or in-place modifications.
+    when_to_use: |
+      - Rotate image 90 degrees
+      - Spiral matrix traversal
+      - Set matrix zeroes
+      - Transpose matrix
+      - Game of Life state updates
+
+  - name: Synchronization
+    slug: synchronization
+    description: Coordinate multiple threads or processes using locks, semaphores, or barriers.
+    when_to_use: |
+      - Print in order problems
+      - Producer-consumer patterns
+      - Dining philosophers
+      - Building H2O molecules
+      - Concurrent data structure design

backend/data/questions/01-matrix.yaml

@@ -7,9 +7,12 @@ categories:
   - arrays
   - graphs
 patterns:
-  - bfs
+  - slug: bfs
-  - matrix-traversal
+    is_optimal: true
-  - dynamic-programming
+  - slug: matrix-traversal
+    is_optimal: false
+  - slug: dynamic-programming
+    is_optimal: false
 
 function_signature: "def update_matrix(mat: list[list[int]]) -> list[list[int]]:"
 

backend/data/questions/132-pattern.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - stack
 patterns:
-  - monotonic-stack
+  - slug: monotonic-stack
+    is_optimal: true
 
 function_signature: "def find132pattern(nums: list[int]) -> bool:"
 

backend/data/questions/2-keys-keyboard.yaml

@@ -7,7 +7,8 @@ categories:
   - dynamic-programming
   - math
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def min_steps(n: int) -> int:"
 

backend/data/questions/24-game.yaml

@@ -8,7 +8,8 @@ categories:
   - math
   - recursion
 patterns:
-  - backtracking
+  - slug: backtracking
+    is_optimal: true
 
 function_signature: "def judge_point24(cards: list[int]) -> bool:"
 

backend/data/questions/3sum-with-multiplicity.yaml

@@ -8,7 +8,8 @@ categories:
   - hash-tables
   - two-pointers
 patterns:
-  - two-pointers
+  - slug: counting-sort
+    is_optimal: true
 
 function_signature: "def three_sum_multi(arr: list[int], target: int) -> int:"
 

backend/data/questions/4sum-ii.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - hash-tables
 patterns:
-  - two-pointers
+  - slug: hashing
+    is_optimal: true
 
 function_signature: "def four_sum_count(nums1: list[int], nums2: list[int], nums3: list[int], nums4: list[int]) -> int:"
 

backend/data/questions/a-number-after-a-double-reversal.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/a-number-after-a-double-reversal/
 categories:
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def is_same_after_reversals(num: int) -> bool:"
 

backend/data/questions/accounts-merge.yaml

@@ -8,8 +8,10 @@ categories:
   - hash-tables
   - strings
 patterns:
-  - union-find
+  - slug: union-find
-  - dfs
+    is_optimal: true
+  - slug: dfs
+    is_optimal: false
 
 function_signature: "def accounts_merge(accounts: list[list[str]]) -> list[list[str]]:"
 

backend/data/questions/add-binary.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - math
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def add_binary(a: str, b: str) -> str:"
 

backend/data/questions/add-digits.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/add-digits/
 categories:
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def add_digits(num: int) -> int:"
 

backend/data/questions/add-minimum-number-of-rungs.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/add-minimum-number-of-rungs/
 categories:
   - arrays
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def add_rungs(rungs: list[int], dist: int) -> int:"
 

backend/data/questions/add-one-row-to-tree.yaml

@@ -8,9 +8,12 @@ categories:
   - queue
   - recursion
 patterns:
-  - bfs
+  - slug: bfs
-  - dfs
+    is_optimal: true
-  - tree-traversal
+  - slug: dfs
+    is_optimal: false
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def add_one_row(root: TreeNode, val: int, depth: int) -> TreeNode:"
 

backend/data/questions/add-strings.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - math
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def add_strings(num1: str, num2: str) -> str:"
 

backend/data/questions/add-to-array-form-of-integer.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def add_to_array_form(num: list[int], k: int) -> list[int]:"
 

backend/data/questions/add-two-integers.yaml

@@ -5,7 +5,9 @@ leetcode_id: 2235
 leetcode_url: https://leetcode.com/problems/add-two-integers/
 categories:
   - math
-patterns: []
+patterns:
+  - slug: bit-manipulation
+    is_optimal: true
 
 function_signature: "def sum(num1: int, num2: int) -> int:"
 

backend/data/questions/add-two-numbers-ii.yaml

@@ -8,7 +8,8 @@ categories:
   - stack
   - math
 patterns:
-  - linkedlist-reversal
+  - slug: linkedlist-reversal
+    is_optimal: true
 
 function_signature: "def add_two_numbers(l1: ListNode, l2: ListNode) -> ListNode:"
 

backend/data/questions/add-two-numbers.yaml

@@ -7,7 +7,8 @@ categories:
   - linked-lists
   - math
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def add_two_numbers(l1: ListNode | None, l2: ListNode | None) -> ListNode | None:"
 

backend/data/questions/adding-spaces-to-a-string.yaml

@@ -8,7 +8,8 @@ categories:
   - arrays
   - two-pointers
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def add_spaces(s: str, spaces: list[int]) -> str:"
 

backend/data/questions/adding-two-negabinary-numbers.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def add_negabinary(arr1: list[int], arr2: list[int]) -> list[int]:"
 

backend/data/questions/additive-number.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - recursion
 patterns:
-  - backtracking
+  - slug: backtracking
+    is_optimal: true
 
 function_signature: "def is_additive_number(num: str) -> bool:"
 

backend/data/questions/advantage-shuffle.yaml

@@ -7,8 +7,10 @@ categories:
   - arrays
   - sorting
 patterns:
-  - greedy
+  - slug: greedy
-  - two-pointers
+    is_optimal: false
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def advantage_count(nums1: list[int], nums2: list[int]) -> list[int]:"
 

backend/data/questions/airplane-seat-assignment-probability.yaml

@@ -7,7 +7,8 @@ categories:
   - math
   - dynamic-programming
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def nth_person_gets_nth_seat(n: int) -> float:"
 

backend/data/questions/alert-using-same-key.yaml

@@ -9,7 +9,8 @@ categories:
   - strings
   - sorting
 patterns:
-  - sliding-window
+  - slug: sliding-window
+    is_optimal: true
 
 function_signature: "def alert_names(key_name: list[str], key_time: list[str]) -> list[str]:"
 

backend/data/questions/all-divisions-with-highest-score-of-binary-array.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/all-divisions-with-the-highest-score
 categories:
   - arrays
 patterns:
-  - prefix-sum
+  - slug: prefix-sum
+    is_optimal: true
 
 function_signature: "def max_score_indices(nums: list[int]) -> list[int]:"
 

backend/data/questions/all-elements-in-two-binary-search-trees.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - sorting
 patterns:
-  - tree-traversal
+  - slug: tree-traversal
-  - two-pointers
+    is_optimal: false
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def get_all_elements(root1: TreeNode, root2: TreeNode) -> list[int]:"
 

backend/data/questions/all-nodes-distance-k-in-binary-tree.yaml

@@ -8,8 +8,10 @@ categories:
   - graphs
   - hash-tables
 patterns:
-  - bfs
+  - slug: bfs
-  - dfs
+    is_optimal: true
+  - slug: dfs
+    is_optimal: false
 
 function_signature: "def distance_k(root: TreeNode, target: TreeNode, k: int) -> list[int]:"
 

backend/data/questions/all-paths-from-source-to-target.yaml

@@ -7,8 +7,10 @@ categories:
   - graphs
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - backtracking
+    is_optimal: true
+  - slug: backtracking
+    is_optimal: false
 
 function_signature: "def all_paths_source_target(graph: list[list[int]]) -> list[list[int]]:"
 

backend/data/questions/all-possible-full-binary-trees.yaml

@@ -8,8 +8,10 @@ categories:
   - recursion
   - dynamic-programming
 patterns:
-  - backtracking
+  - slug: backtracking
-  - dynamic-programming
+    is_optimal: false
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def all_possible_fbt(n: int) -> list[TreeNode]:"
 

backend/data/questions/allocate-mailboxes.yaml

@@ -9,7 +9,8 @@ categories:
   - sorting
   - math
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def min_distance(houses: list[int], k: int) -> int:"
 

backend/data/questions/alphabet-board-path.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - hash-tables
 patterns:
-  - matrix-traversal
+  - slug: matrix-traversal
+    is_optimal: true
 
 function_signature: "def alphabet_board_path(target: str) -> str:"
 

backend/data/questions/alternating-digit-sum.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/alternating-digit-sum/
 categories:
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def alternate_digit_sum(n: int) -> int:"
 

backend/data/questions/ambiguous-coordinates.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - recursion
 patterns:
-  - backtracking
+  - slug: backtracking
+    is_optimal: true
 
 function_signature: "def ambiguous_coordinates(s: str) -> list[str]:"
 

backend/data/questions/amount-of-time-for-binary-tree-to-be-infected.yaml

@@ -8,8 +8,10 @@ categories:
   - graphs
   - hash-tables
 patterns:
-  - bfs
+  - slug: bfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def amount_of_time(root: TreeNode, start: int) -> int:"
 

backend/data/questions/angle-between-hands-of-a-clock.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/angle-between-hands-of-a-clock/
 categories:
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def angle_clock(hour: int, minutes: int) -> float:"
 

backend/data/questions/append-characters-to-string-to-make-subsequence.yaml

@@ -7,8 +7,10 @@ categories:
   - strings
   - two-pointers
 patterns:
-  - two-pointers
+  - slug: two-pointers
-  - greedy
+    is_optimal: true
+  - slug: greedy
+    is_optimal: false
 
 function_signature: "def append_characters(s: str, t: str) -> int:"
 

backend/data/questions/append-k-integers-with-minimal-sum.yaml

@@ -8,7 +8,8 @@ categories:
   - math
   - sorting
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def min_sum(nums: list[int], k: int) -> int:"
 

backend/data/questions/apply-bitwise-operations-to-make-strings-equal.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def make_strings_equal(s: str, target: str) -> bool:"
 

backend/data/questions/apply-operations-to-an-array.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - two-pointers
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def apply_operations(nums: list[int]) -> list[int]:"
 

backend/data/questions/arithmetic-slices-ii-subsequence.yaml

@@ -8,7 +8,8 @@ categories:
   - dynamic-programming
   - hash-tables
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def number_of_arithmetic_slices(nums: list[int]) -> int:"
 

backend/data/questions/arithmetic-slices.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def number_of_arithmetic_slices(nums: list[int]) -> int:"
 

backend/data/questions/arithmetic-subarrays.yaml

@@ -8,7 +8,8 @@ categories:
   - hash-tables
   - sorting
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def check_arithmetic_subarrays(nums: list[int], l: list[int], r: list[int]) -> list[bool]:"
 

backend/data/questions/arranging-coins.yaml

@@ -7,7 +7,8 @@ categories:
   - math
   - binary-search
 patterns:
-  - binary-search
+  - slug: binary-search
+    is_optimal: true
 
 function_signature: "def arrange_coins(n: int) -> int:"
 

backend/data/questions/array-nesting.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/array-nesting/
 categories:
   - arrays
 patterns:
-  - dfs
+  - slug: dfs
+    is_optimal: true
 
 function_signature: "def array_nesting(nums: list[int]) -> int:"
 

backend/data/questions/array-of-doubled-pairs.yaml

@@ -8,7 +8,8 @@ categories:
   - hash-tables
   - sorting
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def can_reorder_doubled(arr: list[int]) -> bool:"
 

backend/data/questions/array-partition.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - sorting
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def array_pair_sum(nums: list[int]) -> int:"
 

backend/data/questions/array-with-elements-not-equal-to-average-of-neighbors.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - sorting
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def rearrange_array(nums: list[int]) -> list[int]:"
 

backend/data/questions/as-far-from-land-as-possible.yaml

@@ -7,8 +7,10 @@ categories:
   - arrays
   - graphs
 patterns:
-  - bfs
+  - slug: bfs
-  - matrix-traversal
+    is_optimal: true
+  - slug: matrix-traversal
+    is_optimal: false
 
 function_signature: "def max_distance(grid: list[list[int]]) -> int:"
 

backend/data/questions/assign-cookies.yaml

@@ -8,8 +8,10 @@ categories:
   - sorting
   - two-pointers
 patterns:
-  - greedy
+  - slug: greedy
-  - two-pointers
+    is_optimal: false
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def find_content_children(g: list[int], s: list[int]) -> int:"
 

backend/data/questions/asteroid-collision.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - stack
 patterns:
-  - monotonic-stack
+  - slug: monotonic-stack
+    is_optimal: true
 
 function_signature: "def asteroid_collision(asteroids: list[int]) -> list[int]:"
 

backend/data/questions/available-captures-for-rook.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/available-captures-for-rook/
 categories:
   - arrays
 patterns:
-  - matrix-traversal
+  - slug: matrix-traversal
+    is_optimal: true
 
 function_signature: "def num_rook_captures(board: list[list[str]]) -> int:"
 

backend/data/questions/average-of-levels-in-binary-tree.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - queue
 patterns:
-  - bfs
+  - slug: bfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def average_of_levels(root: TreeNode) -> list[float]:"
 

backend/data/questions/average-salary-excluding-minimum-and-maximum.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - sorting
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def average(salary: list[int]) -> float:"
 

backend/data/questions/average-value-of-even-numbers-divisible-by-three.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - prefix-sum
+  - slug: prefix-sum
+    is_optimal: true
 
 function_signature: "def average_value(nums: list[int]) -> int:"
 

backend/data/questions/average-waiting-time.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/average-waiting-time/
 categories:
   - arrays
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def average_waiting_time(customers: list[list[int]]) -> float:"
 

backend/data/questions/avoid-flood-in-the-city.yaml

@@ -7,8 +7,10 @@ categories:
   - arrays
   - hash-tables
 patterns:
-  - greedy
+  - slug: greedy
-  - binary-search
+    is_optimal: false
+  - slug: binary-search
+    is_optimal: true
 
 function_signature: "def avoid_flood(rains: list[int]) -> list[int]:"
 

backend/data/questions/backspace-string-compare.yaml

@@ -8,7 +8,8 @@ categories:
   - stack
   - two-pointers
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def backspace_compare(s: str, t: str) -> bool:"
 

backend/data/questions/bag-of-tokens.yaml

@@ -8,8 +8,10 @@ categories:
   - sorting
   - two-pointers
 patterns:
-  - two-pointers
+  - slug: two-pointers
-  - greedy
+    is_optimal: true
+  - slug: greedy
+    is_optimal: false
 
 function_signature: "def bag_of_tokens_score(tokens: list[int], power: int) -> int:"
 

backend/data/questions/balance-a-binary-search-tree.yaml

@@ -6,8 +6,10 @@ leetcode_url: https://leetcode.com/problems/balance-a-binary-search-tree/
 categories:
   - trees
 patterns:
-  - tree-traversal
+  - slug: tree-traversal
-  - dfs
+    is_optimal: true
+  - slug: dfs
+    is_optimal: false
 
 function_signature: "def balance_bst(root: TreeNode) -> TreeNode:"
 

backend/data/questions/balanced-binary-tree.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def is_balanced(root: TreeNode) -> bool:"
 

backend/data/questions/base-7.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def convert_to_base7(num: int) -> str:"
 

backend/data/questions/baseball-game.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - stack
 patterns:
-  - monotonic-stack
+  - slug: monotonic-stack
+    is_optimal: true
 
 function_signature: "def cal_points(operations: list[str]) -> int:"
 

backend/data/questions/basic-calculator-ii.yaml

@@ -8,7 +8,8 @@ categories:
   - stack
   - math
 patterns:
-  - monotonic-stack
+  - slug: monotonic-stack
+    is_optimal: true
 
 function_signature: "def calculate(s: str) -> int:"
 

backend/data/questions/basic-calculator-iv.yaml

@@ -10,7 +10,8 @@ categories:
   - stack
   - math
 patterns:
-  - backtracking
+  - slug: backtracking
+    is_optimal: true
 
 function_signature: "def basic_calculator_iv(expression: str, evalvars: list[str], evalints: list[int]) -> list[str]:"
 

backend/data/questions/basic-calculator.yaml

@@ -8,7 +8,8 @@ categories:
   - stack
   - math
 patterns:
-  - monotonic-stack
+  - slug: monotonic-stack
+    is_optimal: true
 
 function_signature: "def calculate(s: str) -> int:"
 

backend/data/questions/battleships-in-a-board.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - graphs
 patterns:
-  - matrix-traversal
+  - slug: matrix-traversal
+    is_optimal: true
 
 function_signature: "def count_battleships(board: list[list[str]]) -> int:"
 

backend/data/questions/beautiful-arrangement-ii.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def construct_array(n: int, k: int) -> list[int]:"
 

backend/data/questions/beautiful-arrangement.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - recursion
 patterns:
-  - backtracking
+  - slug: backtracking
+    is_optimal: true
 
 function_signature: "def count_arrangement(n: int) -> int:"
 

backend/data/questions/beautiful-array.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def beautiful_array(n: int) -> list[int]:"
 

backend/data/questions/best-poker-hand.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - hash-tables
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def best_hand(ranks: list[int], suits: list[str]) -> str:"
 

backend/data/questions/best-position-for-a-service-centre.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def get_min_dist_sum(positions: list[list[int]]) -> float:"
 

backend/data/questions/best-sightseeing-pair.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def max_score_sightseeing_pair(values: list[int]) -> int:"
 

backend/data/questions/best-team-with-no-conflicts.yaml

@@ -8,7 +8,8 @@ categories:
   - dynamic-programming
   - sorting
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def best_team_score(scores: list[int], ages: list[int]) -> int:"
 

backend/data/questions/best-time-to-buy-and-sell-stock-ii.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def max_profit(prices: list[int]) -> int:"
 

backend/data/questions/best-time-to-buy-and-sell-stock-iii.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def max_profit(prices: list[int]) -> int:"
 

backend/data/questions/best-time-to-buy-and-sell-stock-iv.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def max_profit(k: int, prices: list[int]) -> int:"
 

backend/data/questions/best-time-to-buy-and-sell-stock-with-cooldown.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
+    is_optimal: true
 
 function_signature: "def max_profit(prices: list[int]) -> int:"
 

backend/data/questions/best-time-to-buy-and-sell-stock-with-transaction-fee.yaml

@@ -7,8 +7,10 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - dynamic-programming
+  - slug: dynamic-programming
-  - greedy
+    is_optimal: true
+  - slug: greedy
+    is_optimal: false
 
 function_signature: "def max_profit(prices: list[int], fee: int) -> int:"
 

backend/data/questions/best-time-to-buy-and-sell-stock.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - dynamic-programming
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def max_profit(prices: list[int]) -> int:"
 

backend/data/questions/binary-gap.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/binary-gap/
 categories:
   - math
 patterns:
-  - two-pointers
+  - slug: two-pointers
+    is_optimal: true
 
 function_signature: "def binary_gap(n: int) -> int:"
 

backend/data/questions/binary-number-with-alternating-bits.yaml

@@ -6,7 +6,8 @@ leetcode_url: https://leetcode.com/problems/binary-number-with-alternating-bits/
 categories:
   - math
 patterns:
-  - greedy
+  - slug: greedy
+    is_optimal: true
 
 function_signature: "def has_alternating_bits(n: int) -> bool:"
 

backend/data/questions/binary-prefix-divisible-by-5.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - math
 patterns:
-  - prefix-sum
+  - slug: prefix-sum
+    is_optimal: true
 
 function_signature: "def prefixes_div_by5(nums: list[int]) -> list[bool]:"
 

backend/data/questions/binary-search-tree-iterator.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - stack
 patterns:
-  - tree-traversal
+  - slug: tree-traversal
-  - monotonic-stack
+    is_optimal: false
+  - slug: monotonic-stack
+    is_optimal: true
 
 function_signature: "class BSTIterator:\n    def __init__(self, root: TreeNode): ...\n    def next(self) -> int: ...\n    def hasNext(self) -> bool: ..."
 

backend/data/questions/binary-search-tree-to-greater-sum-tree.yaml

@@ -6,8 +6,10 @@ leetcode_url: https://leetcode.com/problems/binary-search-tree-to-greater-sum-tr
 categories:
   - trees
 patterns:
-  - dfs
+  - slug: dfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def bst_to_gst(root: TreeNode) -> TreeNode:"
 

backend/data/questions/binary-search.yaml

@@ -7,7 +7,8 @@ categories:
   - arrays
   - binary-search
 patterns:
-  - binary-search
+  - slug: binary-search
+    is_optimal: true
 
 function_signature: "def search(nums: list[int], target: int) -> int:"
 

backend/data/questions/binary-string-with-substrings-representing-1-to-n.yaml

@@ -7,7 +7,8 @@ categories:
   - strings
   - math
 patterns:
-  - sliding-window
+  - slug: sliding-window
+    is_optimal: true
 
 function_signature: "def query_string(s: str, n: int) -> bool:"
 

backend/data/questions/binary-subarrays-with-sum.yaml

@@ -7,8 +7,10 @@ categories:
   - arrays
   - hash-tables
 patterns:
-  - sliding-window
+  - slug: sliding-window
-  - prefix-sum
+    is_optimal: true
+  - slug: prefix-sum
+    is_optimal: false
 
 function_signature: "def num_subarrays_with_sum(nums: list[int], goal: int) -> int:"
 

backend/data/questions/binary-tree-cameras.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - dynamic-programming
 patterns:
-  - dfs
+  - slug: dfs
-  - greedy
+    is_optimal: true
+  - slug: greedy
+    is_optimal: false
 
 function_signature: "def min_camera_cover(root: TreeNode) -> int:"
 

backend/data/questions/binary-tree-coloring-game.yaml

@@ -6,8 +6,10 @@ leetcode_url: https://leetcode.com/problems/binary-tree-coloring-game/
 categories:
   - trees
 patterns:
-  - dfs
+  - slug: dfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def btree_game_winning_move(root: TreeNode, n: int, x: int) -> bool:"
 

backend/data/questions/binary-tree-inorder-traversal.yaml

@@ -8,8 +8,10 @@ categories:
   - stack
   - recursion
 patterns:
-  - tree-traversal
+  - slug: tree-traversal
-  - dfs
+    is_optimal: true
+  - slug: dfs
+    is_optimal: false
 
 function_signature: "def inorder_traversal(root: TreeNode) -> list[int]:"
 

backend/data/questions/binary-tree-level-order-traversal-ii.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - queue
 patterns:
-  - bfs
+  - slug: bfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def level_order_bottom(root: TreeNode) -> list[list[int]]:"
 

backend/data/questions/binary-tree-level-order-traversal.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - queue
 patterns:
-  - bfs
+  - slug: bfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def level_order(root: TreeNode | None) -> list[list[int]]:"
 

backend/data/questions/binary-tree-maximum-path-sum.yaml

@@ -8,8 +8,10 @@ categories:
   - dynamic-programming
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - dynamic-programming
+    is_optimal: true
+  - slug: dynamic-programming
+    is_optimal: false
 
 function_signature: "def max_path_sum(root: TreeNode) -> int:"
 

backend/data/questions/binary-tree-paths.yaml

@@ -8,9 +8,12 @@ categories:
   - strings
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - backtracking
+    is_optimal: true
-  - tree-traversal
+  - slug: backtracking
+    is_optimal: false
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def binary_tree_paths(root: TreeNode) -> list[str]:"
 

backend/data/questions/binary-tree-postorder-traversal.yaml

@@ -8,8 +8,10 @@ categories:
   - stack
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def postorder_traversal(root: TreeNode) -> list[int]:"
 

backend/data/questions/binary-tree-preorder-traversal.yaml

@@ -8,8 +8,10 @@ categories:
   - stack
   - recursion
 patterns:
-  - tree-traversal
+  - slug: tree-traversal
-  - dfs
+    is_optimal: true
+  - slug: dfs
+    is_optimal: false
 
 function_signature: "def preorder_traversal(root: TreeNode) -> list[int]:"
 

backend/data/questions/binary-tree-pruning.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def prune_tree(root: TreeNode) -> TreeNode:"
 

backend/data/questions/binary-tree-right-side-view.yaml

@@ -6,9 +6,12 @@ leetcode_url: https://leetcode.com/problems/binary-tree-right-side-view/
 categories:
   - trees
 patterns:
-  - bfs
+  - slug: bfs
-  - dfs
+    is_optimal: true
-  - tree-traversal
+  - slug: dfs
+    is_optimal: false
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def right_side_view(root: TreeNode) -> list[int]:"
 

backend/data/questions/binary-tree-tilt.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - recursion
 patterns:
-  - dfs
+  - slug: dfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def find_tilt(root: TreeNode) -> int:"
 

backend/data/questions/binary-tree-zigzag-level-order-traversal.yaml

@@ -7,8 +7,10 @@ categories:
   - trees
   - queue
 patterns:
-  - bfs
+  - slug: bfs
-  - tree-traversal
+    is_optimal: true
+  - slug: tree-traversal
+    is_optimal: false
 
 function_signature: "def zigzag_level_order(root: TreeNode) -> list[list[int]]:"