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No.	Problem Title	Organization	Solution	Algorithm	Time Complexity
1	A. Numbers	Codeforces	1.cpp	math
2	A. Fashion in Berland	Codeforces	2.cpp	logic
3	A. Night at the Museum	Codeforces	3.cpp	logic
4	A. Bear and Game	Codeforces	4.cpp	logic
5	A. Arrays	Codeforces	5.cpp	sort
6	A. Vitaly and Strings	Codeforces	6.cpp	logic
7	B. African Crossword	Codeforces	7.cpp	logic
8	B. Big Segment	Codeforces	8.cpp	logic
9	B. Passwords	Codeforces	9.cpp	math
10	A. Dress'em in Vests!	Codeforces	10.cpp	logic
11	A. Sereja and Dima	Codeforces	11.cpp	logic
12	B. Approximating a Constant Range	Codeforces	12.cpp	2-pointers
13	B. Array	Codeforces	13.cpp	2-pointers
14	B. Balls Game	Codeforces	14.cpp	2-pointers
15	B. Books	Codeforces	15.cpp	2-pointers
16	B. George and Round	Codeforces	16.cpp	2-pointers
17	C. Alice, Bob and Chocolate	Codeforces	17.cpp	2-pointers
18	A. Business trip	Codeforces	18.cpp	sort
19	A. Chores	Codeforces	19.cpp	sort
20	A. GukiZ and Contest	Codeforces	20.cpp	sort
21	A. Towers	Codeforces	21.cpp	logic
22	B. Devu, the Dumb Guy	Codeforces	22.cpp	sort
23	B. Eight Point Sets	Codeforces	23.cpp	sort, logic
24	B. Pasha and Tea	Codeforces	24.cpp	sort, logic
25	B. Sort the Array	Codeforces	25.cpp	sort, logic, 2-pointers
26	Compilers and parsers	Codechef	26.cpp	greedy
27	MMASS - Mass of Molecule	SPOJ	27.cpp	stack
28	STPAR - Street Parade	SPOJ	28.cpp	stack
29	ONP - Transform the Expression	SPOJ	29.cpp	stack
30	10935 - Throwing cards away I	UVA	30.cpp	queue
31	12207 - That is Your Queue	UVA	31.cpp	queue
32	10901 - Ferry Loading III	UVA	32.cpp	queue
33	UCV2013H - Slick	SPOJ	33.py	bfs
34	MAKEMAZE - VALIDATE THE MAZE	SPOJ	34.py	bfs
35	Guilty Prince	LightOJ	35.py	bfs
36	Dhoom 4	HackerEarth	36.py	bfs
37	Breadth First Search: Shortest Reach	HackerRank	37.py	bfs
38	C. Ice Cave	Codeforces	38.py	bfs
39	Valid Parentheses	LeetCode	39.py	logic
40	C. Kefa and Park	Codeforces	40.py	bfs
41	1610 - Dudu Service Maker	UVA	41.py	dfs
42	D. Lakes in Berland	Codeforces	42.py	dfs
43	CAM5 - prayatna PR	SPOJ	43.cpp	dfs
44	BENEFACT - The Benefactor	SPOJ	44.py	dfs
45	LASTSHOT - THE LAST SHOT	SPOJ	45.go	dfs
46	10954 - Add All	UVA	46.py	heap
47	11995 - I Can Guess the Data Structure!	UVA	47.py	heap, stack,queue
48	Monk and Multiplication	HackerEarth	48.py	heap
49	QHEAP1	HackerRank	49.py	heap
50	Restaurant Rating	CodeChef	50.py	heap
51	Roy and Trending Topics	HackerEarth	51.py	heap
52	Two Sum	LeetCode	52.py	logic
53	Ransom Note	LeetCode	53.py	logic
54	Best Time to Buy and Sell Stock II	LeetCode	54.py	logic
55	Palindrome Number	LeetCode	55.py	logic
56	Roman to Integer	LeetCode	56.py	logic
57	Longest Common Prefix	LeetCode	57.py	sort
58	Summary Ranges	LeetCode	58.py	logic
59	Equal Row and Column Pairs	LeetCode	59.py	hash
60	Minimum Absolute Difference in BST	LeetCode	60.py	dfs
61	Maximum Level Sum of a Binary Tree	LeetCode	61.py	dfs
62	Bishu and his Girlfriend	HackerEarth	62.cpp	dfs
63	ALLIZWEL - ALL IZZ WELL	SPOJ	63.py	dfs
64	1726. Tuple with Same Product	LeetCode	64.py	sorting, 2-pointers, math
65	2. Add Two Numbers	LeetCode	65.py	linked-list
66	4. Median of Two Sorted Arrays	LeetCode	66.py	sort
67	3. Longest Substring Without Repeating Characters	LeetCode	67.py	2-pointers
68	2576. Find the Maximum Number of Marked Indices	LeetCode	68.py	2-pointers, sort
69	966. Vowel Spellchecker	LeetCode	69.py	logic
70	2239. Find Closest Number to Zero	LeetCode	70.py	logic
71	3160. Find the Number of Distinct Colors Among the Balls	LeetCode	71.py	queue, dict
72	3043. Find the Length of the Longest Common Prefix	LeetCode	72.py	trie
73	TRVCOST - Travelling cost	SPOJ	73.py	dijkstra
74	MICEMAZE - Mice and Maze	SPOJ	74.py	dijkstra
75	SHPATH - The Shortest Path	SPOJ	75.cpp	dijkstra
76	10986 - Sending email	UVA	76.py	dijkstra
77	Commandos	LightOJ	77.cpp	dijkstra
78	TRAFFICN - Traffic Network	SPOJ	78.cpp	dijkstra
79	558 - Wormholes	UVA	79.py	bellman
80	Extended Traffic	LightOJ	80.cpp	bellman
81	UCV2013B - Alice in Amsterdam, I mean Wonderland	SPOJ	81.cpp	bellman
82	Monk's Business Day	HackerRank	82.py	bellman
83	515. Find Largest Value in Each Tree Row	LeetCode	83.py	sort, binary-tree
84	ARBITRAG - Arbitrage	SPOJ	84.py	floy-warshall
85	278. First Bad Version	LeetCode	85.py	binary-search
86	10171 - Meeting Prof. Miguel...	UVA	86.py	floy-warshall
87	10246 - Asterix and Obelix	UVA	87.py	floy-warshall
88	2349. Design a Number Container System	LeetCode	88.py	heap
89	2364. Count Number of Bad Pairs	LeetCode	89.py	logic, math
90	3174. Clear Digits	LeetCode	90.py	stack
91	3289. The Two Sneaky Numbers of Digitville	LeetCode	91.py	logic
92	2739. Total Distance Traveled	LeetCode	92.py	logic
93	1910. Remove All Occurrences of a Substring	LeetCode	93.py	stack
94	2816. Double a Number Represented as a Linked List	LeetCode	94.py	linked-list
95	2342. Max Sum of a Pair With Equal Sum of Digits	LeetCode	95.py	logic
96	3066. Minimum Operations to Exceed Threshold Value II	LeetCode	96.py	heap
97	1352. Product of the Last K Numbers	LeetCode	97.py	logic
98	2698. Find the Punishment Number of an Integer	LeetCode	98.py	recursive
99	1718. Construct the Lexicographically Largest Valid Sequence	LeetCode	99.py	recursive
100	1079. Letter Tile Possibilities	LeetCode	100.py	back-tracking, set	$$O(n \cdot n!)$$
101	2375. Construct Smallest Number From DI String	LeetCode	101.py	back-tracking, set	$$O(n \cdot n!)$$
102	1415. The k-th Lexicographical String of All Happy Strings of Length n	LeetCode	102.py	back-tracking, set, sort	$$O(n!)$$
103	1980. Find Unique Binary String	LeetCode	103.py	back-tracking	$$O(n!)$$
104	1261. Find Elements in a Contaminated Binary Tree	LeetCode	104.py	back-tracking	$$O(n)$$
105	3325. Count Substrings With K-Frequency Characters I	LeetCode	105.py	logic	$$O(n)$$
106 ⭐	1028. Recover a Tree From Preorder Traversal	LeetCode	106.py	bin-tree, back-tracking	$$O(n)$$
107 ⭐	889. Construct Binary Tree from Preorder and Postorder Traversal	LeetCode	107.py	bin-tree, back-tracking	$$O(n^2)$$
108 ⭐	2467. Most Profitable Path in a Tree	LeetCode	108.py	dfs	$$O(n)$$
109	21. Merge Two Sorted Lists	LeetCode	109.java	logic	$$O(n)$$
110	35. Search Insert Position	LeetCode	110.js	binary-search	$$O(log(n))$$
111 ⭐	1524. Number of Sub-arrays With Odd Sum	LeetCode	111.py	dp	$$O(n)$$
112 ⭐	1749. Maximum Absolute Sum of Any Subarray	LeetCode	112.py	greedy	$$O(n)$$
113 ⭐	873. Length of Longest Fibonacci Subsequence	LeetCode	113.go	dp	$$O(n^2)$$
114 ⭐	1092. Shortest Common Supersequence	LeetCode	114.py	dp	$$O(n \cdot m)$$
115	2460. Apply Operations to an Array	LeetCode	115.go	logic	$$O(n)$$
116	2570. Merge Two 2D Arrays by Summing Values	LeetCode	116.js	logic	$$O(m + n)$$
117	2161. Partition Array According to Given Pivot	LeetCode	117.ts	logic	$$O(n)$$
118	1780. Check if Number is a Sum of Powers of Three	LeetCode	118.js	logic	$$O(16)$$
119	2579. Count Total Number of Colored Cells	LeetCode	119.go	logic	$$O(n / 2)$$
120	2965. Find Missing and Repeated Values	LeetCode	120.py	logic	$$O(n^2)$$
121	2523. Closest Prime Numbers in Range	LeetCode	121.go	logic	$$O(n\cdot log(log(n)))$$
122	2379. Minimum Recolors to Get K Consecutive Black Blocks	LeetCode	122.go	logic	$$O(n)$$
123	876. Middle of the Linked List	LeetCode	123.go	logic	$$O(n)$$
124	3208. Alternating Groups II	LeetCode	124.js	2-pointers	$$O(n + k)$$
125	1358. Number of Substrings Containing All Three Characters	LeetCode	125.py	slide-window	$$O(n)$$
126	2529. Maximum Count of Positive Integer and Negative Integer	LeetCode	126.py	logic	$$O(n)$$
127	3306. Count of Substrings Containing Every Vowel and K Consonants II	LeetCode	127.py	slide-window	$$O(n)$$
128	88. Merge Sorted Array	LeetCode	128.py	sort	$$O(log(n))$$
129	2226. Maximum Candies Allocated to K Children	LeetCode	129.py	binary-search	$$O(n log(m))$$ with $m$ is the maximum value in the array $candies$, and $n$ is the length of $candies$
130 ⭐	3356. Zero Array Transformation II	LeetCode	130.py	binary-search	$$O(n log(n))$$
131 ⭐	2560. House Robber IV	LeetCode	131.py	binary-search	$$O(n log(n))$$
132 ⭐	2594. Minimum Time to Repair Cars	LeetCode	132.java	binary-search	$$O(n log(n))$$
133	2206. Divide Array Into Equal Pairs	LeetCode	133.java	logic	$$O(max(n, 500))$$
134	1976. Number of Ways to Arrive at Destination	LeetCode	134.py	dijkstra	$$O((N + E)log(N))$$
135	2685. Count the Number of Complete Components	LeetCode	135.py	dfs	$$O(n+mlogn) \text{ and } O(n+m)$$
136	2033. Minimum Operations to Make a Uni-Value Grid	LeetCode	136.py	sort, math	$$O(n \cdot logn)$$
137	2780. Minimum Index of a Valid Split	LeetCode	137.py	logic	$$O(n)$$
138	3169. Count Days Without Meetings	LeetCode	138.py	sort	$$O(log(n))$$
139	3191. Minimum Operations to Make Binary Array Elements Equal to One I	LeetCode	139.py	sliding-window	$$O(n)$$
140	2401. Longest Nice Subarray	LeetCode	140.py	sliding-window	$$O(n)$$
141 ⭐	763. Partition Labels	LeetCode	141.py	2-pointers	$$O(n)$$
142 ⭐	2140. Solving Questions With Brainpower	LeetCode	142.py	dp	$$O(n)$$
143	2874. Maximum Value of an Ordered Triplet II	LeetCode	143.py	greedy	$$O(n)$$
144	1123. Lowest Common Ancestor of Deepest Leaves	LeetCode	144.py	dfs, backtracking	$$O(n)$$
145	1863. Sum of All Subset XOR Totals	LeetCode	145.py	backtracking	$$O(2^n)$$
146	198. House Robber	LeetCode	146.py	dp	$$O(n)$$
147	368. Largest Divisible Subset	LeetCode	147.py	dp	$$O(n^2)$$
148	416. Partition Equal Subset Sum	LeetCode	148.py	dp	$$O(n^2)$$
149	2843. Count Symmetric Integers	LeetCode	149.py	logic	$$O(n)$$
150	3396. Minimum Number of Operations to Make Elements in Array Distinct	LeetCode	150.java	logic	$$O(n)$$