DSA-CRACKER

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• Added Clone A Graph problem in the Graphs topic.

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Hello, folks!

This is an attempt to solve 450 questions carefully curated by our very own Love Babbar.

Topics

• Array
• Matrix
• Stack & Queue
• Backtracking
• Graphs

Array

#	Title	Solution	Time	Space	Difficulty	Note
1	Reverse an Array	✔️	-	-	-	-
2	Find the maximum and minimum element in an array	✔️	-	-	-	-
3	Find the "Kth" max and min element of an array	✔️	-	-	-	-
4	Given an array which consists of only 0, 1 and 2. Sort the array without using any sorting algo	✔️	-	-	-	-
5	Move all the negative elements to one side of the array	✔️	-	-	-
6	Find the Union and Intersection of the two sorted arrays.	✔️	-	-	-	-
7	Write a program to cyclically rotate an array by one.	✔️	-	-	-	-
8	find Largest sum contiguous Subarray V. IMP	✔️	-	-	-	-
9	Minimise the maximum difference between heights V.IMP	✔️	-	-	-	Revisit
10	Minimum no. of Jumps to reach end of an array	✔️	-	-	-	Revisit
11	find duplicate in an array of N+1 Integers	✔️	-	-	-	-
12	Merge 2 sorted arrays without using Extra space.	✔️	-	-	-	Revisit
13	Kadane's Algo [V.V.V.V.V IMP]	✔️	-	-	-	-
14	Merge Intervals	✔️	-	-	-	-
15	Next Permutation	✔️	-	-	-	-
16	Count Inversion	✔️	-	-	-	-
17	Best time to buy and Sell stock	✔️	-	-	-	Pending variations
18	find all pairs on integer array whose sum is equal to given number	✔️	-	-	-	-
19	find common elements In 3 sorted arrays	✔️	-	-	-	-
20	Rearrange the array in alternating positive and negative items with O(1) extra space	✔️	-	-	-	-
21	Find if there is any subarray with sum equal to 0	✔️	-	-	-	-
22	Find factorial of a large number	✔️	-	-	-
23	find maximum product subarray	✔️	-	-	-	-
24	Find longest coinsecutive subsequence	✔️	-	-	-	-
25	Given an array of size n and a number k, fin all elements that appear more than " n/k " times.	✔️	-	-	-	-
26	Maximum profit by buying and selling a share atmost twice	✔️	-	-	-	-
27	Find whether an array is a subset of another array	✔️	-	-	-
28	Find the triplet that sum to a given value	✔️	-	-	-	-
29	Trapping Rain water problem	✔️	-	-	-	Revisit
30	Chocolate Distribution problem	✔️	-	-	-	-
31	Smallest Subarray with sum greater than a given value		-	-	-	XXXX
32	Three way partitioning of an array around a given value	✔️	-	-	-
33	Minimum swaps required bring elements less equal K together	✔️	-	-	-	-
34	Minimum no. of operations required to make an array palindrome	✔️	-	-	-	-
35	Median of 2 sorted arrays of equal size	✔️	-	-	-	Revisit
36	Median of 2 sorted arrays of different size	✔️	-	-	-	-

Matrix

StackQueue

#	Title	Solution	Time	Space	Difficulty	Note
1	Implement Stack from Scratch	✔️	-	-	-
2	https://www.tutorialspoint.com/javaexamples/data_stack.htm	✔️	-	-	-	-
3	Implement 2 stack in an array	✔️	-	-	-	-
4	Find the middle element of a stack		-	-	-	-
5	Implement "N" stacks in an Array	✔️	-	-	-
6	Check the expression has valid or Balanced parenthesis or not.	✔️	-	-	-	-
7	Reverse a String using Stack	✔️	-	-	-	-
8	Design a Stack that supports getMin() in O(1) time and O(1) extra space.	✔️	-	-	-	-
9	Find the next Greater element	✔️	-	-	-	-
10	The celebrity Problem	✔️	-	-	-	-
11	Arithmetic Expression evaluation	✔️	-	-	-	-
12	Evaluation of Postfix expression	✔️	-	-	-	-
13	Implement a method to insert an element at its bottom without using any other data structure.	✔️	-	-	-	-
14	Reverse a stack using recursion	✔️	-	-	-	-
15	Sort a Stack using recursion	✔️	-	-	-	-
16	Merge Overlapping Intervals	✔️	O(n*logn)	O(1)	-	-
17	Largest rectangular Area in Histogram	✔️	O(n)	O(n)	-	-
18	Length of the Longest Valid Substring	✔️	O(n)	O(1)	-	-
19	Expression contains redundant bracket or not	✔️	O(n)	O(n)	-	-
20	Implement Stack using Queue	✔️	O(n)	O(n)	-	-

Backtracking

Graphs

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