counting Problems | Design Gurus

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counting

53 problems

#	Title	Acceptance	Difficulty
1	Contains Duplicate (easy) array hash set sorting +1 more	55.4%	easy
2	Pangram (easy) string hash set counting +1 more	30.9%	easy
3	Valid Anagram (easy) string hash map counting +1 more	38.2%	easy
4	Shortest Word Distance (easy) array string two pointers +2 more	27.7%	easy
5	Number of Good Pairs (easy) array counting hash map +1 more	75.3%	easy
6	Triplets with Smaller Sum (medium) array two pointers sorting +1 more	22.5%	Med.
7	Longest Substring with K Distinct Characters (medium) sliding window string hash map +1 more	27.9%	Med.
8	Longest Substring with Same Letters after Replacement (hard) sliding window string hash map +2 more	29.8%	hard
9	Longest Subarray with Ones after Replacement (hard) sliding window array two pointers +1 more	48.6%	hard
10	Problem Challenge 1: Permutation in a String (hard) sliding window hash map string +2 more	16.2%	hard
11	Problem Challenge 4: Words Concatenation (hard) sliding window hash map string +1 more	23.1%	hard
12	Problem Challenge 5: Counting Subarrays with Product Less than a Target (hard) sliding window two pointers array +1 more	29.0%	hard
13	Find the Missing Number (easy) cyclic sort bitwise xor array +2 more	42.4%	easy
14	Problem Challenge 1: Find the Corrupt Pair (easy) cyclic sort array sorting +1 more	47.9%	easy
15	Problem Challenge 2: Find the Smallest Missing Positive Number (medium) cyclic sort array sorting +1 more	28.8%	Med.
16	Problem Challenge 3: Find the First K Missing Positive Numbers (hard) cyclic sort array sorting +1 more	16.6%	hard
17	Remove All Adjacent Duplicates in String II (medium) stack string counting +2 more	37.0%	Med.
18	Sum of Subarray Minimums (medium) monotonic stack array stack +1 more	67.6%	Med.
19	Problem 1: First Non-repeating Character (easy) string hash map counting	55.3%	easy
20	Solution: First Non-repeating Character (easy) hash map string counting +1 more	0.0%	easy
21	Problem 2: Largest Unique Number (easy) array counting hash map +1 more	61.4%	easy
22	Solution: Largest Unique Number (easy) hash map array counting +1 more	0.0%	easy
23	Problem 3: Maximum Number of Balloons (easy) string counting hash map	39.7%	easy
24	Solution: Maximum Number of Balloons (easy) hash map string counting +1 more	0.0%	easy
25	Problem 4: Longest Palindrome(easy) string hash map greedy algorithm +1 more	24.1%	easy
26	Solution: Longest Palindrome(easy) string hash map counting +1 more	0.0%	easy
27	Problem 5: Ransom Note (easy) string hash map counting +1 more	56.7%	easy
28	Solution: Ransom Note (easy) hash map string counting +2 more	0.0%	easy
29	Maximum Width of Binary Tree (medium) binary tree tree breadth first search level order traversal +3 more	32.1%	Med.
30	Minimum Number of Vertices to Reach All Nodes(medium) graph graph algorithms counting	45.0%	Med.
31	Solution: Minimum Number of Vertices to Reach All Nodes(medium) graph graph algorithms counting +1 more	0.0%	Med.
32	Number of Islands (easy) matrix traversal graph depth-first search +4 more	49.1%	easy
33	Problem Challenge 1 (easy) matrix simulation counting +1 more	27.2%	easy
34	Problem Challenge 3: Count of Structurally Unique Binary Search Trees (hard) binary search tree dynamic programming recursion +2 more	34.3%	hard
35	Single Number (easy) array bitwise xor hash map +2 more	82.5%	easy
36	Top 'K' Frequent Numbers (medium) top k elements hash map heap +3 more	55.9%	Med.
37	Frequency Sort (medium) string hash map sorting +2 more	80.5%	Med.
38	Maximum Distinct Elements (medium) greedy algorithm hash map heap +3 more	22.6%	Med.
39	Problem Challenge 2: Scheduling Tasks (hard) greedy algorithm priority queue heap +3 more	33.1%	hard
40	Problem Challenge 3: Frequency Stack (hard) stack hash map counting +2 more	40.0%	hard
41	Minimum Add to Make Parentheses Valid (medium) string stack greedy algorithm +2 more	48.3%	Med.
42	Remove Duplicate Letters (medium) string monotonic stack greedy algorithm +3 more	17.9%	Med.
43	Largest Palindromic Number (medium) string greedy algorithm counting +1 more	15.3%	Med.
44	Factor Combinations (medium) backtracking recursion subsets +1 more	36.3%	Med.
45	Merge Similar Items (easy) array hash map sorting +2 more	83.4%	easy
46	Binary Subarrays With Sum (medium) array sliding window prefix sum +2 more	56.6%	Med.
47	Subarray Sums Divisible by K (medium) array prefix sum hash map +1 more	50.5%	Med.
48	Design Parking System (easy) simulation counting array	92.1%	easy
49	Valid Sudoku (medium) matrix hash set matrix traversal +3 more	35.7%	Med.
50	Decode Ways (medium) dynamic programming string recursion +1 more	17.2%	Med.
51	Unique Paths (medium) dynamic programming matrix traversal recursion +2 more	65.3%	Med.
52	Longest Consecutive Sequence (medium) hash set array counting	31.9%	Med.
53	Longest Valid Parentheses (hard) string stack dynamic programming +2 more	15.5%	hard