Yandex LeetCode Questions

128 questions all-time · 51 easy · 67 medium · 10 hard

#	Problem	Difficulty	Frequency	Acceptance
1	Longest Subarray of 1's After Deleting One Element Array, Dynamic Programming, Sliding Window	Medium	100	0.7%
2	Summary Ranges Array	Easy	90	0.5%
3	Maximize Distance to Closest Person Array	Medium	89	0.5%
4	Longest Substring Without Repeating Characters Hash Table, String, Sliding Window	Medium	84	0.4%
5	Find K Closest Elements Array, Two Pointers, Binary Search, Sliding Window, Sorting, Heap (Priority Queue)	Medium	83	0.5%
6	Subarray Sum Equals K Array, Hash Table, Prefix Sum	Medium	80	0.5%
7	String Compression Two Pointers, String	Medium	79	0.6%
8	Merge Intervals Array, Sorting	Medium	79	0.5%
9	Valid Palindrome II Two Pointers, String, Greedy	Easy	79	0.4%
10	Move Zeroes Array, Two Pointers	Easy	76	0.6%
11	One Edit Distance Two Pointers, String	Medium	73	0.3%
12	Isomorphic Strings Hash Table, String	Easy	72	0.5%
13	Permutation in String Hash Table, Two Pointers, String, Sliding Window	Medium	72	0.5%
14	Line Reflection Array, Hash Table, Math	Medium	71	0.4%
15	Two Sum Array, Hash Table	Easy	70	0.6%
16	Longest Palindromic Substring Two Pointers, String, Dynamic Programming	Medium	70	0.4%
17	Valid Palindrome Two Pointers, String	Easy	70	0.5%
18	Longest Strictly Increasing or Strictly Decreasing Subarray Array	Easy	70	0.6%
19	Find All Anagrams in a String Hash Table, String, Sliding Window	Medium	69	0.5%
20	Find the Prefix Common Array of Two Arrays Array, Hash Table, Bit Manipulation	Medium	68	0.9%
21	Number of Islands Array, Depth-First Search, Breadth-First Search, Union-Find, Matrix	Medium	67	0.6%
22	Insert Delete GetRandom O(1) Array, Hash Table, Math, Design, Randomized	Medium	67	0.6%
23	Group Anagrams Array, Hash Table, String, Sorting	Medium	66	0.7%
24	Merge Sorted Array Array, Two Pointers, Sorting	Easy	65	0.6%
25	Interval List Intersections Array, Two Pointers, Sweep Line	Medium	63	0.7%
26	Trapping Rain Water Array, Two Pointers, Dynamic Programming, Stack, Monotonic Stack	Hard	62	0.7%
27	Squares of a Sorted Array Array, Two Pointers, Sorting	Easy	62	0.7%
28	Valid Parentheses String, Stack	Easy	60	0.4%
29	Merge Two Sorted Lists Linked List, Recursion	Easy	60	0.7%
30	Design an ATM Machine Array, Greedy, Design	Medium	60	0.5%
31	Is Subsequence Two Pointers, String, Dynamic Programming	Easy	60	0.5%
32	Find Duplicate Subtrees Hash Table, Tree, Depth-First Search, Binary Tree	Medium	59	0.6%
33	Min Stack Stack, Design	Medium	57	0.6%
34	Max Consecutive Ones III Array, Binary Search, Sliding Window, Prefix Sum	Medium	55	0.7%
35	Binary Tree Right Side View Tree, Depth-First Search, Breadth-First Search, Binary Tree	Medium	55	0.7%
36	Lowest Common Ancestor of a Binary Tree Tree, Depth-First Search, Binary Tree	Medium	55	0.7%
37	Product of Array Except Self Array, Prefix Sum	Medium	55	0.7%
38	Median of Two Sorted Arrays Array, Binary Search, Divide and Conquer	Hard	53	0.5%
39	Container With Most Water Array, Two Pointers, Greedy	Medium	53	0.6%
40	Merge k Sorted Lists Linked List, Divide and Conquer, Heap (Priority Queue), Merge Sort	Hard	53	0.6%
41	Symmetric Tree Tree, Depth-First Search, Breadth-First Search, Binary Tree	Easy	53	0.6%
42	LRU Cache Hash Table, Linked List, Design, Doubly-Linked List	Medium	53	0.5%
43	Perfect Squares Math, Dynamic Programming, Breadth-First Search	Medium	53	0.6%
44	Reconstruct Itinerary Array, String, Depth-First Search, Graph Theory, Sorting, Heap (Priority Queue), Eulerian Circuit	Hard	53	0.4%
45	Generate Parentheses String, Dynamic Programming, Backtracking	Medium	50	0.8%
46	Search in Rotated Sorted Array Array, Binary Search	Medium	50	0.5%
47	Binary Tree Maximum Path Sum Dynamic Programming, Tree, Depth-First Search, Binary Tree	Hard	50	0.4%
48	Longest Substring with At Most K Distinct Characters Hash Table, String, Sliding Window	Medium	50	0.5%
49	Design Hit Counter Array, Binary Search, Design, Queue, Data Stream	Medium	50	0.7%
50	Count Substrings Without Repeating Character Hash Table, String, Sliding Window	Medium	50	0.8%
51	Remove Element Array, Two Pointers	Easy	47	0.6%
52	Number of Recent Calls Design, Queue, Data Stream	Easy	47	0.8%
53	Maximum Subarray Array, Divide and Conquer, Dynamic Programming	Medium	47	0.5%
54	Add Two Numbers Linked List, Math, Recursion	Medium	44	0.5%
55	Simplify Path String, Stack	Medium	44	0.5%
56	Reverse Linked List Linked List, Recursion	Easy	44	0.8%
57	Longest Repeating Character Replacement Hash Table, String, Sliding Window	Medium	44	0.6%
58	Destination City Array, Hash Table, String	Easy	44	0.8%
59	Can Place Flowers Array, Greedy	Easy	44	0.3%
60	Basic Calculator II Math, String, Stack	Medium	44	0.5%
61	Remove Duplicates from Sorted Array Array, Two Pointers	Easy	44	0.6%
62	Binary Tree Zigzag Level Order Traversal Tree, Breadth-First Search, Binary Tree	Medium	40	0.6%
63	Best Time to Buy and Sell Stock Array, Dynamic Programming	Easy	40	0.6%
64	Longest Increasing Subsequence Array, Binary Search, Dynamic Programming	Medium	40	0.6%
65	Intersection of Two Arrays Array, Hash Table, Two Pointers, Binary Search, Sorting	Easy	40	0.8%
66	Max Consecutive Ones Array	Easy	40	0.7%
67	Product of Two Run-Length Encoded Arrays Array, Two Pointers	Medium	40	0.6%
68	Longest Continuous Increasing Subsequence Array	Easy	40	0.5%
69	4Sum Array, Two Pointers, Sorting	Medium	40	0.4%
70	Minimum Window Substring Hash Table, String, Sliding Window	Hard	34	0.5%
71	Find Minimum in Rotated Sorted Array Array, Binary Search	Medium	34	0.5%
72	Lowest Common Ancestor of a Binary Search Tree Tree, Depth-First Search, Binary Search Tree, Binary Tree	Medium	34	0.7%
73	Intersection of Two Arrays II Array, Hash Table, Two Pointers, Binary Search, Sorting	Easy	34	0.6%
74	Continuous Subarray Sum Array, Hash Table, Math, Prefix Sum	Medium	34	0.3%
75	Monotonic Array Array	Easy	34	0.6%
76	Range Sum of BST Tree, Depth-First Search, Binary Search Tree, Binary Tree	Easy	34	0.9%
77	Letter Combinations of a Phone Number Hash Table, String, Backtracking	Medium	34	0.7%
78	Implement Queue using Stacks Stack, Design, Queue	Easy	34	0.7%
79	Design an Ordered Stream Array, Hash Table, Design, Data Stream	Easy	34	0.8%
80	Remove Nth Node From End of List Linked List, Two Pointers	Medium	34	0.5%
81	Binary Tree Level Order Traversal Tree, Breadth-First Search, Binary Tree	Medium	34	0.7%
82	Find Median from Data Stream Two Pointers, Design, Sorting, Heap (Priority Queue), Data Stream	Hard	34	0.5%
83	Add Strings Math, String, Simulation	Easy	34	0.5%
84	Linked List Cycle Hash Table, Linked List, Two Pointers	Easy	34	0.5%
85	Matrix Diagonal Sum Array, Matrix	Easy	34	0.8%
86	Sliding Window Maximum Array, Queue, Sliding Window, Heap (Priority Queue), Monotonic Queue	Hard	34	0.5%
87	Allow One Function Call	Easy	34	0.9%
88	Function Composition	Easy	34	0.9%
89	Reverse Integer Math	Medium	27	0.3%
90	Validate Binary Search Tree Tree, Depth-First Search, Binary Search Tree, Binary Tree	Medium	27	0.4%
91	Two Sum II - Input Array Is Sorted Array, Two Pointers, Binary Search	Medium	27	0.7%
92	Majority Element Array, Hash Table, Divide and Conquer, Sorting, Counting	Easy	27	0.7%
93	Palindrome Linked List Linked List, Two Pointers, Stack, Recursion	Easy	27	0.6%
94	Valid Anagram Hash Table, String, Sorting	Easy	27	0.7%
95	First Unique Character in a String Hash Table, String, Queue, Counting	Easy	27	0.7%
96	Longest Substring with At Least K Repeating Characters Hash Table, String, Divide and Conquer, Sliding Window	Medium	27	0.5%
97	Jewels and Stones Hash Table, String	Easy	27	0.9%
98	Text Justification Array, String, Simulation	Hard	27	0.5%
99	Coin Change Array, Dynamic Programming, Breadth-First Search	Medium	27	0.5%
100	Merge Two 2D Arrays by Summing Values Array, Hash Table, Two Pointers	Easy	27	0.8%
101	Implement Rand10() Using Rand7() Math, Rejection Sampling, Randomized, Probability and Statistics	Medium	27	0.5%
102	Daily Temperatures Array, Stack, Monotonic Stack	Medium	27	0.7%
103	Swap Nodes in Pairs Linked List, Recursion	Medium	27	0.7%
104	Lowest Common Ancestor of a Binary Tree III Hash Table, Two Pointers, Tree, Binary Tree	Medium	27	0.8%
105	Create Hello World Function	Easy	27	0.8%
106	Cinema Seat Allocation Array, Hash Table, Greedy, Bit Manipulation	Medium	27	0.4%
107	Counter II	Easy	27	0.8%
108	Search Insert Position Array, Binary Search	Easy	27	0.5%
109	Path Crossing Hash Table, String	Easy	27	0.6%
110	Rotting Oranges Array, Breadth-First Search, Matrix	Medium	27	0.6%
111	Employees Earning More Than Their Managers Database	Easy	27	0.7%
112	Maximum Average Subarray I Array, Sliding Window	Easy	27	0.5%
113	Find the Difference of Two Arrays Array, Hash Table	Easy	27	0.8%
114	Find Common Elements Between Two Arrays Array, Hash Table	Easy	27	0.8%
115	Subarray Sums Divisible by K Array, Hash Table, Prefix Sum	Medium	27	0.6%
116	Minimum Size Subarray Sum Array, Binary Search, Sliding Window, Prefix Sum	Medium	27	0.5%
117	Search a 2D Matrix Array, Binary Search, Matrix	Medium	27	0.5%
118	Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit Array, Queue, Sliding Window, Heap (Priority Queue), Ordered Set, Monotonic Queue	Medium	27	0.6%
119	Evaluate Reverse Polish Notation Array, Math, Stack	Medium	27	0.6%
120	Maximum Product of Two Elements in an Array Array, Sorting, Heap (Priority Queue)	Easy	27	0.8%
121	Spiral Matrix Array, Matrix, Simulation	Medium	27	0.6%
122	Zigzag Iterator Array, Design, Queue, Iterator	Medium	27	0.7%
123	Binary Search Array, Binary Search	Easy	27	0.6%
124	Meeting Scheduler Array, Two Pointers, Sorting	Medium	27	0.6%
125	Top K Frequent Elements Array, Hash Table, Divide and Conquer, Sorting, Heap (Priority Queue), Bucket Sort, Counting, Quickselect	Medium	27	0.7%
126	Palindrome Number Math	Easy	27	0.6%
127	Subarrays with K Different Integers Array, Hash Table, Sliding Window, Counting	Hard	27	0.7%
128	Add Binary Math, String, Bit Manipulation, Simulation	Easy	27	0.6%

How to read this list

The tabs at the top split the questions by how recently people said they were asked in interviews. "Last 30 Days" is the past month, "Last 3 Months" is the past quarter, and so on. "All Time" is every question on record for this company.

Frequency is a score from 0 to 100 for how often a question showed up in that time window. A higher number means it came up more often, so the list starts with the most common questions first. Acceptance is the share of submissions that pass on LeetCode. Click any question to open it on LeetCode.