Problem Sets | Design Gurus

Core Pillars

Patterns

Difficulty

# Title Acceptance Difficulty
1 Contains Duplicate (easy) 55.5% easy
2 Pangram (easy) 31.1% easy
3 Reverse Vowels (easy) 44.3% easy
4 Valid Palindrome (easy) 22.6% easy
5 Valid Anagram (easy) 38.4% easy
6 Shortest Word Distance (easy) 27.9% easy
7 Number of Good Pairs (easy) 75.4% easy
8 Sqrt (medium) 15.4% Med.
9 Pair with Target Sum (easy) 42.4% easy
10 Find Non-Duplicate Number Instances (easy) 42.5% easy
11 Squaring a Sorted Array (easy) 35.6% easy
12 Triplet Sum to Zero (medium) 22.2% Med.
13 Triplet Sum Close to Target (medium) 12.2% Med.
14 Triplets with Smaller Sum (medium) 22.7% Med.
15 Dutch National Flag Problem (medium) 29.6% Med.
16 Problem Challenge 1: Quadruple Sum to Target (medium) 17.3% Med.
17 Problem Challenge 2: Comparing Strings containing Backspaces (medium) 16.8% Med.
18 Problem Challenge 3: Minimum Window Sort (medium) 12.7% Med.
19 LinkedList Cycle (easy) 64.5% easy
20 Middle of the LinkedList (easy) 59.9% easy
21 Start of LinkedList Cycle (medium) 49.7% Med.
22 Happy Number (medium) 47.2% Med.
23 Problem Challenge 1: Palindrome LinkedList (medium) 28.9% Med.
24 Problem Challenge 2: Rearrange a LinkedList (medium) 56.3% Med.
25 Problem Challenge 3: Cycle in a Circular Array (hard) 17.2% hard
26 Maximum Sum Subarray of Size K (easy) 46.3% easy
27 Smallest Subarray With a Greater Sum (easy) 19.7% easy
28 Longest Substring with K Distinct Characters (medium) 28.0% Med.
29 Fruits into Baskets (medium) 39.5% Med.
30 Longest Substring with Same Letters after Replacement (hard) 29.9% hard
31 Longest Subarray with Ones after Replacement (hard) 48.7% hard
32 Problem Challenge 1: Permutation in a String (hard) 16.3% hard
33 Problem Challenge 2: String Anagrams (hard) 29.1% hard
34 Problem Challenge 3: Smallest Window containing Substring (hard) 20.0% hard
35 Problem Challenge 4: Words Concatenation (hard) 23.2% hard
36 Problem Challenge 5: Counting Subarrays with Product Less than a Target (hard) 29.0% hard
37 Problem Challenge 6: Subarrays with Product Less than a Target (hard) 24.8% hard
38 Merge Intervals (medium) 31.3% Med.
39 Insert Interval (medium) 22.0% Med.
40 Intervals Intersection (medium) 48.0% Med.
41 Conflicting Appointments (medium) 28.1% Med.
42 Problem Challenge 1: Minimum Meeting Rooms (hard) 25.8% hard
43 Problem Challenge 2: Maximum CPU Load (hard) 43.1% hard
44 Problem Challenge 3: Employee Free Time (hard) 48.4% hard
45 Cyclic Sort (easy) 48.3% easy
46 Find the Missing Number (easy) 42.5% easy
47 Find all Missing Numbers (easy) 54.3% easy
48 Find the Duplicate Number (easy) 49.1% easy
49 Find all Duplicate Numbers (easy) 67.2% easy
50 Problem Challenge 1: Find the Corrupt Pair (easy) 48.1% easy
51 Problem Challenge 2: Find the Smallest Missing Positive Number (medium) 28.9% Med.
52 Problem Challenge 3: Find the First K Missing Positive Numbers (hard) 16.7% hard
53 Reverse a LinkedList (easy) 80.1% easy
54 Reverse a Sub-list (medium) 31.4% Med.
55 Reverse every K-element Sub-list (medium) 53.1% Med.
56 Problem Challenge 1: Reverse alternating K-element Sub-list (medium) 51.7% Med.
57 Problem Challenge 2: Rotate a LinkedList (medium) 22.9% Med.
58 Problem 1: Balanced Parentheses (easy) 30.1% easy
59 Problem 2: Reverse a String (easy) 85.1% easy
60 Problem 3: Decimal to Binary Conversion (medium) 46.7% Med.
61 Problem 4: Next Greater Element (easy) 31.5% easy
62 Problem 5: Sorting a Stack (easy) 69.7% easy
63 Problem 6: Simplify Path (medium) 25.2% Med.
64 Remove Nodes From Linked List (easy) 41.9% easy
65 Remove All Adjacent Duplicates In String (easy) 58.6% easy
66 Next Greater Element (easy) 55.4% easy
67 Daily Temperatures (easy) 54.9% easy
68 Remove All Adjacent Duplicates in String II (medium) 37.1% Med.
69 Sum of Subarray Minimums (medium) 67.6% Med.
70 Remove K Digits (hard) 12.6% hard
71 Problem 1: First Non-repeating Character (easy) 55.3% easy
72 Solution: First Non-repeating Character (easy) 0.0% easy
73 Problem 2: Largest Unique Number (easy) 61.4% easy
74 Solution: Largest Unique Number (easy) 0.0% easy
75 Problem 3: Maximum Number of Balloons (easy) 39.7% easy
76 Solution: Maximum Number of Balloons (easy) 0.0% easy
77 Problem 4: Longest Palindrome (easy) 24.1% easy
78 Solution: Longest Palindrome (easy) 0.0% easy
79 Problem 5: Ransom Note (easy) 56.7% easy
80 Solution: Ransom Note (easy) 0.0% easy
81 Binary Tree Level Order Traversal (easy) 73.5% easy
82 Reverse Level Order Traversal (easy) 89.2% easy
83 Zigzag Traversal (medium) 64.1% Med.
84 Level Averages in a Binary Tree (easy) 82.0% easy
85 Find Largest Value in Each Tree Row (medium) 90.5% Med.
86 Maximum Level Sum of a Binary Tree (medium) 54.0% Med.
87 Even Odd Tree (medium) 56.9% Med.
88 Minimum Depth of a Binary Tree (easy) 21.5% easy
89 Level Order Successor (easy) 63.9% easy
90 Connect Level Order Siblings (medium) 78.1% Med.
91 Maximum Width of Binary Tree (medium) 32.1% Med.
92 N-ary Tree Level Order Traversal (hard) 92.5% hard
93 Problem Challenge 1: Connect All Level Order Siblings (medium) 80.1% Med.
94 Problem Challenge 2: Right View of a Binary Tree (easy) 76.3% easy
95 Binary Tree Path Sum (easy) 38.3% easy
96 All Paths for a Sum (medium) 56.9% Med.
97 Sum of Path Numbers (medium) 69.0% Med.
98 Path With Given Sequence (medium) 25.9% Med.
99 Count Paths for a Sum (medium) 24.5% Med.
100 Problem Challenge 1: Tree Diameter (medium) 59.3% Med.