Voids currated problems.xlsx

	A	B	C	D	E
1	MATH
2	1
3	2	https://leetcode.com/problems/minimum-value-to-get-positive-step-by-step-sum/	https://www.youtube.com/watch?v=SUagl73pWuY&ab_channel=CodingDecoded
4	3	https://leetcode.com/problems/count-integers-with-even-digit-sum/		finding sum of digit mathematically
5	4	https://practice.geeksforgeeks.org/problems/trailing-zeroes-in-factorial5134/1#
6	5	https://leetcode.com/problems/categorize-box-according-to-criteria/		how to multiply numbers which crosses 1e9
7	6	https://leetcode.com/problems/count-odd-numbers-in-an-interval-range/
8	7	https://leetcode.com/problems/check-if-it-is-a-straight-line/	discuss	slope+math+geomentry
9	MEDIUM
10	1	https://leetcode.com/problems/minimum-operations-to-make-array-equal/	https://leetcode.com/problems/minimum-operations-to-make-array-equal/discuss/1145082/Simple-O(1)-1-Liner-or-Easy-Solution-w-Explanation-or-Beats-100	check discuss section
11	2			Goldbach’s Conjecture:Every even integer greater than 2 can be expressed as the sum of two primes.
12	3	https://leetcode.com/problems/ugly-number-ii/	https://www.youtube.com/watch?v=QyeDRMprJVQ&ab_channel=CodingBlocks
13	4	https://leetcode.com/problems/powx-n/		logarithmic time very good idea
14	BIT MANUPLATION
15	EASY
16	1	https://leetcode.com/problems/hamming-distance/
17	2	https://leetcode.com/problems/power-of-two/	https://www.youtube.com/watch?v=GOaRIDmsu74&ab_channel=CodingDecoded	power of 2 trick
18	3	https://leetcode.com/problems/add-binary/	https://www.geeksforgeeks.org/program-binary-decimal-conversion/ https://www.geeksforgeeks.org/program-decimal-binary-conversion/	this is the basics and very good trick is used using carry
19	4	https://leetcode.com/problems/design-bitset/submissions/		not at all intutive
20	5	https://leetcode.com/problems/single-number/	discuss	xor property
21	6	https://leetcode.com/problems/decode-xored-array/		xor property
22	7	https://leetcode.com/problems/number-of-1-bits/
23	8	https://leetcode.com/problems/check-if-a-string-contains-all-binary-codes-of-size-k/
24	ARRAY
25	SNO	PROBLEM	SOLUTION(reference video )	METHOD	REMARK
26	EASY
27	1	https://leetcode.com/problems/maximum-subarray/	https://www.youtube.com/watch?v=w_KEocd__20&list=PLgUwDviBIf0rPG3Ictpu74YWBQ1CaBkm2&index=6&ab_channel=takeUforward	kadenes algorithm to find max sum of sub array
28	2	https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/	https://www.youtube.com/watch?v=xTbj76XN-5U&ab_channel=codeExplainer	nice method use this method if they specify from 1 to n(negative marking technique)
29	3	https://leetcode.com/problems/valid-mountain-array/	https://leetcode.com/problems/valid-mountain-array/discuss/451553/C%2B%2B-Simple-Solution-with-Explanations-for-newbies-less3	mountain array
30	4	https://leetcode.com/problems/majority-element/	https://www.youtube.com/watch?v=n5QY3x_GNDg&ab_channel=TECHDOSE	Boyer-Moore voting algorithm for finding maximum element in a array
31	5	https://leetcode.com/problems/missing-number/	https://leetcode.com/problems/missing-number/discuss/2047948/Solution-with-O(n)-Time-complexity-and-O(1)-space-complexity-with-explanation	good logic using sum of first n natural numbers
32	6	https://leetcode.com/problems/merge-sorted-array/
33	7	https://leetcode.com/problems/valid-anagram/
34	8	https://leetcode.com/problems/pascals-triangle/
35	MEDIUM
36	1	https://leetcode.com/problems/merge-intervals/submissions/	https://www.youtube.com/watch?v=RGr2RuH6iH4&ab_channel=CodeLibrary	using stack
37	2	https://leetcode.com/problems/3sum/submissions/	https://www.youtube.com/watch?v=onLoX6Nhvmg&ab_channel=takeUforward	two pointer-3sum
38	3	https://leetcode.com/problems/product-of-array-except-self/	https://www.youtube.com/watch?v=gREVHiZjXeQ&ab_channel=TECHDOSE	vectors new concept
39	4	https://leetcode.com/problems/next-permutation/	own	next_permutation() stl or new algo
40	5	https://leetcode.com/problems/container-with-most-water/	https://www.youtube.com/watch?v=6PrIRPpTI9Q&ab_channel=NickWhite	two pointer
41	6	https://leetcode.com/problems/valid-triangle-number/	https://leetcode.com/problems/valid-triangle-number/discuss/128135/A-similar-O(n2)-solution-to-3-Sum	two pointer-3sum
42	7	https://leetcode.com/problems/push-dominoes/	https://www.youtube.com/watch?v=2LcdnLGHUHE&ab_channel=CodingDecoded	new method
43	8	https://leetcode.com/problems/partition-array-into-disjoint-intervals/	https://www.youtube.com/watch?v=3nqKLuL0yGk&ab_channel=CodingDecoded	left right new method
44	9	https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3918/		2 pointere
45	10	https://leetcode.com/problems/max-consecutive-ones/	explore very brillient
46	11	https://leetcode.com/problems/find-all-duplicates-in-an-array/	https://www.youtube.com/watch?v=aMsSF1Il3IY&ab_channel=NickWhite	1 to n duplicate so negative marking technique
47	12	https://leetcode.com/problems/insert-delete-getrandom-o1/	https://leetcode.com/problems/insert-delete-getrandom-o1/discuss/85422/AC-C%2B%2B-Solution.-Unordered_map-%2B-Vector	delete a element from a array in 0(1) using a map
48	13	https://leetcode.com/problems/interval-list-intersections/	https://www.youtube.com/watch?v=vRyzvWvTwIk&ab_channel=CodingDecoded	merge intervals
49	14	https://leetcode.com/problems/pairs-of-songs-with-total-durations-divisible-by-60/	https://leetcode.com/problems/pairs-of-songs-with-total-durations-divisible-by-60/discuss/1661803/Easy-C%2B%2B-solution-with-explanation-and-intuition-in-detail	2 pointer+map
50	15	https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/		merge intervals variation
51	16	https://leetcode.com/problems/all-divisions-with-the-highest-score-of-a-binary-array/
52	17	https://leetcode.com/problems/rotate-array/	https://www.youtube.com/watch?v=5VW7442mwEg&ab_channel=CodingDecoded	naive and o(n) space doable. O(1) space very new and need to remember
53	18	https://leetcode.com/problems/4sum-ii/
54	19	https://leetcode.com/problems/contiguous-array/
55	20	https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/
56	21	https://leetcode.com/problems/compare-version-numbers/
57	22	https://leetcode.com/problems/arithmetic-slices/		mine is brute force
58	23	https://leetcode.com/problems/append-k-integers-with-minimal-sum/
59	24	https://leetcode.com/problems/find-the-duplicate-number/		negative marking technique if(input size is 1 to n think of negative marking technique)
60	25	https://leetcode.com/problems/insert-interval/	discuss
61	HARD
62
63	MATRIX
64	EASY
65	1	https://leetcode.com/problems/reshape-the-matrix/
66	2	https://leetcode.com/explore/challenge/card/september-leetcoding-challenge-2021/638/week-3-september-15th-september-21st/3981/
67	3	https://leetcode.com/problems/shift-2d-grid/		shifting matrix( observation skills important)
68	4	https://leetcode.com/problems/convert-1d-array-into-2d-array/
69	5	https://leetcode.com/problems/transpose-matrix/
70	MEDIUM
71	1	https://leetcode.com/problems/set-matrix-zeroes/	https://www.youtube.com/watch?v=M65xBewcqcI&t=342s&ab_channel=takeUforward	new vareity o(1) space comp code------>	https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/614/week-2-august-8th-august-14th/3888/
72	2	https://leetcode.com/problems/rotate-image/	https://www.youtube.com/watch?v=Y72QeX0Efxw&ab_channel=takeUforward , https://leetcode.com/problems/rotate-image/discuss/18872/A-common-method-to-rotate-the-image	transpose
73	3	https://leetcode.com/problems/largest-plus-sign/	https://www.youtube.com/watch?v=QCb0hRt_gCs&ab_channel=CodingDecoded	very good problem
74	4	https://leetcode.com/problems/spiral-matrix/	https://www.youtube.com/watch?v=siKFOI8PNKM&ab_channel=mycodeschool	very important and standard problem
75	5	https://leetcode.com/problems/spiral-matrix-ii/		same logic as spiral matrix
76	6	https://leetcode.com/problems/diagonal-traverse/	https://www.youtube.com/watch?v=-FEeaf3ufIE&ab_channel=NareshGupta	very important and standard problem and pure understanding on maps
77	7	https://leetcode.com/problems/game-of-life/		i did with O(n*,m) space but O(n) space is new
78	8	https://leetcode.com/problems/zigzag-conversion/
79	HARD
80
81
82
83
84
85	PEAK/ONE OR 2 PASS/ 2 POINTER
86		Updated list of problems that involved 1 or 2 passes from left to right/right to left: 53 Maximum Subarray 121 Best Time to Buy and Sell Stock 152 Maximum Product Subarray 238 Product of Array Except Self 739 Daily Temperatures 769 Max Chunks to Make Sorted 770 Max Chunks to Make Sorted II 821 Shortest Distance to a Character 845 Longest Mountain in Array 3-pass: 42. Trapping Rain Water 581. Shortest Unsorted Continuous Subarray
87	EASY
88	1	https://leetcode.com/problems/maximum-difference-between-increasing-elements/		peak finding method,two pointer
89	2	https://leetcode.com/problems/best-time-to-buy-and-sell-stock/		peak finding method
90	3	https://leetcode.com/problems/sort-array-by-parity/		basic 2 pointer use
91	MEDIUM
92	1	https://leetcode.com/problems/boats-to-save-people/		greedy
93	2	https://leetcode.com/problems/longest-mountain-in-array/	https://www.youtube.com/watch?v=VXeukMTbxkw&ab_channel=CodewithAlisha	o(n) new logic
94	3	https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/		classic 2 pointer
95	HARD
96	1	https://leetcode.com/problems/trapping-rain-water/	https://www.youtube.com/watch?v=m18Hntz4go8&list=PLgUwDviBIf0p4ozDR_kJJkONnb1wdx2Ma&index=43
97	SLIDING WINDOW
98		Number of Substrings Containing All Three Characters Count Number of Nice Subarrays Replace the Substring for Balanced String Max Consecutive Ones III Binary Subarrays With Sum Subarrays with K Different Integers Fruit Into Baskets Shortest Subarray with Sum at Least K Minimum Size Subarray Sum
99	1	https://leetcode.com/problems/find-the-k-beauty-of-a-number/		fixed length sliding window using maths
100	MEDIUM