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Tiktok DSA Interview Questions

359 curated coding interview questions directly asked in Tiktok technical rounds, sorted by frequency with recency and difficulty diagnostics.

⚡ Open Interactive Tracker (359 Problems) 🔥 Must-Solve Problem Pool 🏢 All Companies Directory

359 Total Questions

36 (10%) Easy Problems

248 (69%) Medium Problems

75 (21%) Hard Problems

🔥 Most Tested Topics:

Arrays (107)Core DSA (99)Strings (66)Trees (48)Dynamic Programming (18)

📂 Sourced Datasets:

Last 30 daysLast 3 monthsLast 6 monthsAll questionsOlder than 6 months

Showing top 200 of 359 questions. View all 359 in the interactive tracker.

Showing 200 of 200 displayed

ID	Problem	Difficulty	Topic	Pattern	Acceptance	Frequency	Recency
200	Number of Islands	Medium	Graphs	BFS / DFS / Topological Sort	64.4%	100.0%	30d
146	LRU Cache	Medium	Design	Data Structure Design	47.4%	100.0%	3m
787	Cheapest Flights Within K Stops	Medium	Heap	Priority Queue	41.8%	87.5%	3m
886	Possible Bipartition	Medium	Dynamic Programming	State Transition	52.6%	87.5%	3m
207	Course Schedule	Medium	Graphs	BFS / DFS / Topological Sort	51.4%	87.5%	6m
42	Trapping Rain Water	Hard	Core DSA	Two Pointers	67.4%	87.5%	all
210	Course Schedule II	Medium	Graphs	BFS / DFS / Topological Sort	55.5%	87.5%	all
300	Longest Increasing Subsequence	Medium	Dynamic Programming	State Transition	59.4%	87.5%	all
694	Number of Distinct Islands	Medium	Graphs	BFS / DFS / Topological Sort	62.8%	87.5%	all
2334	Subarray With Elements Greater Than Varying Threshold	Hard	Arrays	Sorting / Prefix / Scan	45.5%	87.5%	all
68	Text Justification	Hard	Core DSA	Implementation / Reasoning	51.2%	75.0%	3m
121	Best Time to Buy and Sell Stock	Easy	Core DSA	Implementation / Reasoning	56.8%	75.0%	3m
56	Merge Intervals	Medium	Arrays	Sorting / Prefix / Scan	51.8%	75.0%	3m
78	Subsets	Medium	Backtracking	Backtracking	82.3%	75.0%	3m
1352	Product of the Last K Numbers	Medium	Arrays	Sorting / Prefix / Scan	62.9%	75.0%	3m
215	Kth Largest Element in an Array	Medium	Arrays; Heap	Sorting / Prefix / Scan; Priority Queue	68.9%	75.0%	3m
189	Rotate Array	Medium	Arrays	Sorting / Prefix / Scan	44.9%	75.0%	3m
32	Longest Valid Parentheses	Hard	Strings	Hashing / Sliding Window	38.8%	75.0%	3m
706	Design HashMap	Easy	Design	Data Structure Design	66.6%	75.0%	3m
79	Word Search	Medium	Strings; Binary Search	Hashing / Sliding Window; Binary Search	47.4%	75.0%	3m
904	Fruit Into Baskets	Medium	Core DSA	Implementation / Reasoning	51.1%	75.0%	3m
347	Top K Frequent Elements	Medium	Heap	Priority Queue	66.4%	75.0%	3m
15	3Sum	Medium	Arrays	Sorting / Prefix / Scan	39.1%	75.0%	all
51	N-Queens	Hard	Backtracking	Backtracking	75.5%	75.0%	all
69	Sqrt(x)	Easy	Binary Search	Binary Search	41.8%	75.0%	all
76	Minimum Window Substring	Hard	Arrays; Strings; Trees	Sorting / Prefix / Scan; Hashing / Sliding Window; DFS / BFS; Sliding Window	47.5%	75.0%	all
322	Coin Change	Medium	Dynamic Programming	State Transition	48.4%	75.0%	all
1151	Minimum Swaps to Group All 1's Together	Medium	Arrays	Sorting / Prefix / Scan	61.2%	75.0%	all
3	Longest Substring Without Repeating Characters	Medium	Strings; Trees	Hashing / Sliding Window; DFS / BFS; Sliding Window	39.1%	62.5%	6m
253	Meeting Rooms II	Medium	Greedy	Greedy	52.7%	62.5%	6m
33	Search in Rotated Sorted Array	Medium	Arrays; Binary Search	Sorting / Prefix / Scan; Binary Search	44.9%	62.5%	6m
845	Longest Mountain in Array	Medium	Arrays	Sorting / Prefix / Scan	42.1%	62.5%	6m
1	Two Sum	Easy	Arrays	Sorting / Prefix / Scan; Two Pointers	57.5%	62.5%	all
22	Generate Parentheses	Medium	Strings	Hashing / Sliding Window	78.7%	62.5%	all
39	Combination Sum	Medium	Arrays; Backtracking	Sorting / Prefix / Scan; Backtracking	76.5%	62.5%	all
49	Group Anagrams	Medium	Strings	Hashing / Sliding Window	72.6%	62.5%	all
70	Climbing Stairs	Easy	Dynamic Programming	State Transition	54.1%	62.5%	all
71	Simplify Path	Medium	Core DSA	Implementation / Reasoning	50.6%	62.5%	all
72	Edit Distance	Medium	Dynamic Programming	State Transition	60.6%	62.5%	all
75	Sort Colors	Medium	Arrays	Sorting / Prefix / Scan	69.6%	62.5%	all
93	Restore IP Addresses	Medium	Core DSA	Implementation / Reasoning	56.0%	62.5%	all
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	Trees	DFS / BFS	68.8%	62.5%	all
124	Binary Tree Maximum Path Sum	Hard	Arrays; Trees	Sorting / Prefix / Scan; DFS / BFS	42.3%	62.5%	all
127	Word Ladder	Hard	Strings	Hashing / Sliding Window	45.6%	62.5%	all
140	Word Break II	Hard	Strings; Dynamic Programming	Hashing / Sliding Window; State Transition	55.6%	62.5%	all
139	Word Break	Medium	Strings; Dynamic Programming	Hashing / Sliding Window; State Transition	49.5%	62.5%	all
162	Find Peak Element	Medium	Binary Search	Binary Search	47.0%	62.5%	all
198	House Robber	Medium	Dynamic Programming	State Transition	53.2%	62.5%	all
199	Binary Tree Right Side View	Medium	Trees	DFS / BFS	70.2%	62.5%	all
2145	Count the Hidden Sequences	Medium	Core DSA	Implementation / Reasoning	56.8%	62.5%	all
206	Reverse Linked List	Easy	Linked List	Two Pointers	80.6%	62.5%	all
227	Basic Calculator II	Medium	Stack / Queue	Monotonic Stack / Simulation	46.9%	62.5%	all
329	Longest Increasing Path in a Matrix	Hard	Arrays; Dynamic Programming	Sorting / Prefix / Scan; State Transition	56.6%	62.5%	all
380	Insert Delete GetRandom O(1)	Medium	Core DSA	Implementation / Reasoning	55.4%	62.5%	all
415	Add Strings	Easy	Strings	Hashing / Sliding Window	52.2%	62.5%	all
2402	Meeting Rooms III	Hard	Greedy	Greedy	51.5%	62.5%	all
2414	Length of the Longest Alphabetical Continuous Substring	Medium	Strings; Trees	Hashing / Sliding Window; DFS / BFS	60.7%	62.5%	all
2456	Most Popular Video Creator	Medium	Core DSA	Implementation / Reasoning	45.4%	62.5%	all
2523	Closest Prime Numbers in Range	Medium	Core DSA	Implementation / Reasoning	51.8%	62.5%	all
2640	Find the Score of All Prefixes of an Array	Medium	Arrays	Sorting / Prefix / Scan	73.0%	62.5%	all
670	Maximum Swap	Medium	Arrays	Sorting / Prefix / Scan	52.0%	62.5%	all
678	Valid Parenthesis String	Medium	Strings	Hashing / Sliding Window	40.1%	62.5%	all
695	Max Area of Island	Medium	Graphs	BFS / DFS / Topological Sort	74.0%	62.5%	all
735	Asteroid Collision	Medium	Core DSA	Implementation / Reasoning	47.9%	62.5%	all
772	Basic Calculator III	Hard	Stack / Queue	Monotonic Stack / Simulation	53.3%	62.5%	all
2799	Count Complete Subarrays in an Array	Medium	Arrays	Sorting / Prefix / Scan	76.0%	62.5%	all
815	Bus Routes	Hard	Core DSA	Implementation / Reasoning	47.3%	62.5%	all
1011	Capacity To Ship Packages Within D Days	Medium	Binary Search	Binary Search	73.9%	62.5%	all
3086	Minimum Moves to Pick K Ones	Hard	Arrays	Sorting / Prefix / Scan	21.6%	62.5%	all
1405	Longest Happy String	Medium	Strings	Hashing / Sliding Window	65.5%	62.5%	all
1293	Shortest Path in a Grid with Obstacles Elimination	Hard	Trees	DFS / BFS	46.3%	62.5%	all
1802	Maximum Value at a Given Index in a Bounded Array	Medium	Arrays	Sorting / Prefix / Scan	38.9%	62.5%	all
1860	Incremental Memory Leak	Medium	Core DSA	Implementation / Reasoning	72.8%	62.5%	all
212	Word Search II	Hard	Strings; Binary Search	Hashing / Sliding Window; Binary Search	38.5%	62.5%	all
3389	Minimum Operations to Make Character Frequencies Equal	Hard	Arrays; Strings	Sorting / Prefix / Scan; Hashing / Sliding Window	26.4%	62.5%	all
3441	Minimum Cost Good Caption	Hard	Arrays	Sorting / Prefix / Scan	20.9%	62.5%	all
3474	Lexicographically Smallest Generated String	Hard	Strings; Graphs	Hashing / Sliding Window; BFS / DFS / Topological Sort	53.5%	62.5%	all
1146	Snapshot Array	Medium	Arrays	Sorting / Prefix / Scan	36.8%	62.5%	all
5	Longest Palindromic Substring	Medium	Strings; Trees	Hashing / Sliding Window; DFS / BFS	37.8%	50.0%	6m
394	Decode String	Medium	Strings; Dynamic Programming; Stack / Queue	Hashing / Sliding Window; State Transition; Monotonic Stack / Simulation	62.6%	50.0%	6m
560	Subarray Sum Equals K	Medium	Arrays	Sorting / Prefix / Scan	47.3%	50.0%	6m
128	Longest Consecutive Sequence	Medium	Core DSA	Implementation / Reasoning	47.1%	50.0%	6m
827	Making A Large Island	Hard	Graphs	BFS / DFS / Topological Sort	56.6%	50.0%	6m
739	Daily Temperatures	Medium	Stack / Queue	Monotonic Stack / Simulation	68.7%	50.0%	6m
23	Merge k Sorted Lists	Hard	Arrays; Linked List; Heap	Sorting / Prefix / Scan; Two Pointers; Priority Queue	59.6%	50.0%	6m
297	Serialize and Deserialize Binary Tree	Hard	Trees; Design	DFS / BFS; Data Structure Design	60.8%	50.0%	6m
143	Reorder List	Medium	Linked List	Two Pointers	65.3%	50.0%	6m
887	Super Egg Drop	Hard	Core DSA	Implementation / Reasoning	30.2%	50.0%	6m
84	Largest Rectangle in Histogram	Hard	Core DSA	Implementation / Reasoning	49.9%	50.0%	6m
298	Binary Tree Longest Consecutive Sequence	Medium	Trees	DFS / BFS	54.8%	50.0%	6m
55	Jump Game	Medium	Greedy	Greedy	40.9%	50.0%	6m
239	Sliding Window Maximum	Hard	Arrays	Sorting / Prefix / Scan; Sliding Window	48.8%	50.0%	6m
54	Spiral Matrix	Medium	Arrays	Sorting / Prefix / Scan	56.8%	50.0%	6m
1041	Robot Bounded In Circle	Medium	Core DSA	Implementation / Reasoning	56.5%	50.0%	6m
224	Basic Calculator	Hard	Stack / Queue	Monotonic Stack / Simulation	46.9%	50.0%	6m
20	Valid Parentheses	Easy	Strings	Hashing / Sliding Window	44.2%	50.0%	6m
185	Department Top Three Salaries	Hard	Core DSA	Implementation / Reasoning	60.5%	50.0%	6m
438	Find All Anagrams in a String	Medium	Strings	Hashing / Sliding Window	53.8%	50.0%	6m
1143	Longest Common Subsequence	Medium	Core DSA	Implementation / Reasoning	59.2%	50.0%	6m
10	Regular Expression Matching	Hard	Core DSA	Implementation / Reasoning	31.0%	50.0%	all
11	Container With Most Water	Medium	Core DSA	Two Pointers	60.0%	50.0%	all
14	Longest Common Prefix	Easy	Core DSA	Implementation / Reasoning	47.6%	50.0%	all
25	Reverse Nodes in k-Group	Hard	Trees; Linked List	DFS / BFS; Two Pointers	66.1%	50.0%	all
31	Next Permutation	Medium	Backtracking	Backtracking	45.3%	50.0%	all
34	Find First and Last Position of Element in Sorted Array	Medium	Arrays	Sorting / Prefix / Scan	48.9%	50.0%	all
43	Multiply Strings	Medium	Strings	Hashing / Sliding Window	44.2%	50.0%	all
45	Jump Game II	Medium	Greedy	Greedy	42.9%	50.0%	all
46	Permutations	Medium	Backtracking	Backtracking	81.9%	50.0%	all
47	Permutations II	Medium	Backtracking	Backtracking	63.5%	50.0%	all
53	Maximum Subarray	Medium	Arrays	Sorting / Prefix / Scan	53.3%	50.0%	all
122	Best Time to Buy and Sell Stock II	Medium	Core DSA	Implementation / Reasoning	71.1%	50.0%	all
153	Find Minimum in Rotated Sorted Array	Medium	Arrays; Binary Search	Sorting / Prefix / Scan; Binary Search	54.7%	50.0%	all
165	Compare Version Numbers	Medium	Core DSA	Implementation / Reasoning	46.4%	50.0%	all
209	Minimum Size Subarray Sum	Medium	Arrays	Sorting / Prefix / Scan	51.7%	50.0%	all
236	Lowest Common Ancestor of a Binary Tree	Medium	Trees	DFS / BFS	69.3%	50.0%	all
252	Meeting Rooms	Easy	Greedy	Greedy	59.4%	50.0%	all
269	Alien Dictionary	Hard	Graphs	BFS / DFS / Topological Sort	37.2%	50.0%	all
283	Move Zeroes	Easy	Core DSA	Two Pointers	63.8%	50.0%	all
286	Walls and Gates	Medium	Core DSA	Implementation / Reasoning	64.0%	50.0%	all
295	Find Median from Data Stream	Hard	Heap	Priority Queue	54.5%	50.0%	all
316	Remove Duplicate Letters	Medium	Arrays; Strings	Sorting / Prefix / Scan; Hashing / Sliding Window	53.2%	50.0%	all
395	Longest Substring with At Least K Repeating Characters	Medium	Strings; Trees	Hashing / Sliding Window; DFS / BFS; Sliding Window	46.3%	50.0%	all
399	Evaluate Division	Medium	Core DSA	Implementation / Reasoning	64.2%	50.0%	all
416	Partition Equal Subset Sum	Medium	Arrays; Dynamic Programming	Sorting / Prefix / Scan; State Transition	49.5%	50.0%	all
417	Pacific Atlantic Water Flow	Medium	Core DSA	Implementation / Reasoning	61.0%	50.0%	all
588	Design In-Memory File System	Hard	Design	Data Structure Design	48.4%	50.0%	all
767	Reorganize String	Medium	Strings	Hashing / Sliding Window	57.1%	50.0%	all
875	Koko Eating Bananas	Medium	Binary Search	Binary Search	50.0%	50.0%	all
528	Random Pick with Weight	Medium	Core DSA	Implementation / Reasoning	49.1%	50.0%	all
907	Sum of Subarray Minimums	Medium	Arrays	Sorting / Prefix / Scan	38.6%	50.0%	all
974	Subarray Sums Divisible by K	Medium	Arrays	Sorting / Prefix / Scan	56.3%	50.0%	all
994	Rotting Oranges	Medium	Core DSA	Implementation / Reasoning	58.7%	50.0%	all
1249	Minimum Remove to Make Valid Parentheses	Medium	Arrays; Strings	Sorting / Prefix / Scan; Hashing / Sliding Window	71.5%	50.0%	all
1539	Kth Missing Positive Number	Easy	Arrays; Heap	Sorting / Prefix / Scan; Priority Queue	63.5%	50.0%	all
1530	Number of Good Leaf Nodes Pairs	Medium	Trees	DFS / BFS	71.8%	50.0%	all
3043	Find the Length of the Longest Common Prefix	Medium	Core DSA	Implementation / Reasoning	62.2%	50.0%	all
473	Matchsticks to Square	Medium	Core DSA	Implementation / Reasoning	41.9%	50.0%	all
1071	Greatest Common Divisor of Strings	Easy	Strings	Hashing / Sliding Window	53.8%	50.0%	all
365	Water and Jug Problem	Medium	Core DSA	Implementation / Reasoning	45.7%	50.0%	all
934	Shortest Bridge	Medium	Core DSA	Implementation / Reasoning	59.5%	50.0%	all
211	Design Add and Search Words Data Structure	Medium	Strings; Binary Search; Design	Hashing / Sliding Window; Binary Search; Data Structure Design	48.5%	50.0%	all
2021	Brightest Position on Street	Medium	Trees	DFS / BFS	60.6%	50.0%	all
12	Integer to Roman	Medium	Strings	Hashing / Sliding Window	71.0%	37.5%	all
21	Merge Two Sorted Lists	Easy	Arrays; Linked List	Sorting / Prefix / Scan; Two Pointers	68.3%	37.5%	all
24	Swap Nodes in Pairs	Medium	Trees	DFS / BFS	69.5%	37.5%	all
40	Combination Sum II	Medium	Arrays; Backtracking	Sorting / Prefix / Scan; Backtracking	59.5%	37.5%	all
57	Insert Interval	Medium	Arrays	Sorting / Prefix / Scan	45.2%	37.5%	all
64	Minimum Path Sum	Medium	Arrays; Trees	Sorting / Prefix / Scan; DFS / BFS	68.2%	37.5%	all
80	Remove Duplicates from Sorted Array II	Medium	Arrays	Sorting / Prefix / Scan; Two Pointers	64.7%	37.5%	all
92	Reverse Linked List II	Medium	Linked List	Two Pointers	51.5%	37.5%	all
91	Decode Ways	Medium	Dynamic Programming	State Transition	38.0%	37.5%	all
103	Binary Tree Zigzag Level Order Traversal	Medium	Trees	DFS / BFS	63.7%	37.5%	all
113	Path Sum II	Medium	Arrays; Trees	Sorting / Prefix / Scan; DFS / BFS	62.2%	37.5%	all
123	Best Time to Buy and Sell Stock III	Hard	Core DSA	Implementation / Reasoning	53.7%	37.5%	all
125	Valid Palindrome	Easy	Strings	Hashing / Sliding Window	53.3%	37.5%	all
2050	Parallel Courses III	Hard	Graphs	BFS / DFS / Topological Sort	66.8%	37.5%	all
148	Sort List	Medium	Arrays; Linked List	Sorting / Prefix / Scan; Two Pointers	64.4%	37.5%	all
151	Reverse Words in a String	Medium	Strings	Hashing / Sliding Window	56.4%	37.5%	all
152	Maximum Product Subarray	Medium	Arrays	Sorting / Prefix / Scan	36.4%	37.5%	all
159	Longest Substring with At Most Two Distinct Characters	Medium	Strings; Trees	Hashing / Sliding Window; DFS / BFS; Sliding Window	57.1%	37.5%	all
160	Intersection of Two Linked Lists	Easy	Linked List	Two Pointers	63.7%	37.5%	all
2096	Step-By-Step Directions From a Binary Tree Node to Another	Medium	Trees	DFS / BFS	56.4%	37.5%	all
2115	Find All Possible Recipes from Given Supplies	Medium	Core DSA	Implementation / Reasoning	56.9%	37.5%	all
179	Largest Number	Medium	Core DSA	Implementation / Reasoning	43.1%	37.5%	all
188	Best Time to Buy and Sell Stock IV	Hard	Core DSA	Implementation / Reasoning	50.1%	37.5%	all
213	House Robber II	Medium	Dynamic Programming	State Transition	44.9%	37.5%	all
221	Maximal Square	Medium	Core DSA	Implementation / Reasoning	50.3%	37.5%	all
238	Product of Array Except Self	Medium	Arrays	Sorting / Prefix / Scan	68.9%	37.5%	all
301	Remove Invalid Parentheses	Hard	Strings	Hashing / Sliding Window	49.9%	37.5%	all
305	Number of Islands II	Hard	Graphs	BFS / DFS / Topological Sort	40.6%	37.5%	all
317	Shortest Distance from All Buildings	Hard	Core DSA	Implementation / Reasoning	44.9%	37.5%	all
340	Longest Substring with At Most K Distinct Characters	Medium	Strings; Trees	Hashing / Sliding Window; DFS / BFS; Sliding Window	50.0%	37.5%	all
348	Design Tic-Tac-Toe	Medium	Design	Data Structure Design	58.7%	37.5%	all
358	Rearrange String k Distance Apart	Hard	Strings	Hashing / Sliding Window	40.0%	37.5%	all
74	Search a 2D Matrix	Medium	Arrays; Binary Search	Sorting / Prefix / Scan; Binary Search	53.9%	37.5%	all
378	Kth Smallest Element in a Sorted Matrix	Medium	Arrays; Heap	Sorting / Prefix / Scan; Priority Queue	64.6%	37.5%	all
381	Insert Delete GetRandom O(1) - Duplicates allowed	Hard	Arrays	Sorting / Prefix / Scan	36.6%	37.5%	all
402	Remove K Digits	Medium	Core DSA	Implementation / Reasoning	36.9%	37.5%	all
403	Frog Jump	Hard	Greedy	Greedy	47.3%	37.5%	all
435	Non-overlapping Intervals	Medium	Arrays; Greedy	Sorting / Prefix / Scan; Greedy	57.1%	37.5%	all
443	String Compression	Medium	Strings	Hashing / Sliding Window	60.0%	37.5%	all
456	132 Pattern	Medium	Strings	Hashing / Sliding Window	34.8%	37.5%	all
460	LFU Cache	Hard	Design	Data Structure Design	49.2%	37.5%	all
475	Heaters	Medium	Core DSA	Implementation / Reasoning	41.9%	37.5%	all
2468	Split Message Based on Limit	Hard	Core DSA	Implementation / Reasoning	42.1%	37.5%	all
2422	Merge Operations to Turn Array Into a Palindrome	Medium	Arrays; Strings	Sorting / Prefix / Scan; Hashing / Sliding Window	68.9%	37.5%	all
518	Coin Change II	Medium	Dynamic Programming	State Transition	60.0%	37.5%	all
525	Contiguous Array	Medium	Arrays	Sorting / Prefix / Scan	51.3%	37.5%	all
2506	Count Pairs Of Similar Strings	Easy	Strings	Hashing / Sliding Window	73.7%	37.5%	all
621	Task Scheduler	Medium	Greedy	Greedy	63.1%	37.5%	all
642	Design Search Autocomplete System	Hard	Binary Search; Design	Binary Search; Data Structure Design	50.0%	37.5%	all
658	Find K Closest Elements	Medium	Core DSA	Implementation / Reasoning	49.7%	37.5%	all
662	Maximum Width of Binary Tree	Medium	Arrays; Trees	Sorting / Prefix / Scan; DFS / BFS	45.6%	37.5%	all
673	Number of Longest Increasing Subsequence	Medium	Dynamic Programming	State Transition	51.9%	37.5%	all
680	Valid Palindrome II	Easy	Strings	Hashing / Sliding Window	44.3%	37.5%	all
691	Stickers to Spell Word	Hard	Strings	Hashing / Sliding Window	50.9%	37.5%	all
714	Best Time to Buy and Sell Stock with Transaction Fee	Medium	Core DSA	Implementation / Reasoning	72.0%	37.5%	all
726	Number of Atoms	Hard	Core DSA	Implementation / Reasoning	65.1%	37.5%	all
752	Open the Lock	Medium	Core DSA	Implementation / Reasoning	61.3%	37.5%	all
426	Convert Binary Search Tree to Sorted Doubly Linked List	Medium	Arrays; Trees; Linked List; Binary Search	Sorting / Prefix / Scan; DFS / BFS; Two Pointers; Binary Search	65.6%	37.5%	all

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