DSA 450

This repo is collection of solutions for the 450 dsa question published by Love babbar. All the solutions are written in python progrmming language.

I am using this to keep track of the problems since it allows you to mark problems without actually logging in as it is using the localdb.

Search and Sort

S.no	Problem	Solution
1	Find first and last positions of an element in a sorted array	Link
2	Find a Fixed Point (Value equal to index) in a given array	Link
3	Search in a rotated sorted array	Link
4	Square root of an integer	Link
5	Maximum and minimum of an array using minimum number of comparisons	Link
6	Find the repeating and the missing	Link
7	find majority element	Link
8	Searching in an array where adjacent differ by at most k	Link
9	find a pair with a given difference	Link
10	find four elements that sum to a given value	Link
11	maximum sum such that no 2 elements are adjacent	Link
12	Count triplet with sum smaller than a given value	Link
13	merge 2 sorted arrays	Link
14	print all subarrays with 0 sum	Link
15	Product array Puzzle	Link
16	Sort array according to count of set bits	Link
17	minimum no. of swaps required to sort the array	Link
18	Bishu and Soldiers	Link
19	Kth smallest number again	Link
20	Aggressive cows	Link
21	Book Allocation Problem	Link
22	EKOSPOJ:	Link
23	Job Scheduling Algo	Link
24	Missing Number in AP	Link
25	Smallest number with atleastn trailing zeroes infactorial	Link
26	ROTI-Prata SPOJ	Link
27	DoubleHelix SPOJ	Link
28	Subset Sums	Link
29	Findthe inversion count	Link
30	Implement Merge-sort in-place	Link

Linked List

S.no	Problem	Solution
1	Write a Program to reverse the Linked List. (Both Iterative and recursive)	Link
2	Reverse a Linked List in group of Given Size. [Very Imp]	Link
3	Write a program to Detect loop in a linked list.	Link
4	Write a program to Delete loop in a linked list.	Link
5	Find the starting point of the loop.	Link
6	Remove Duplicates in a sorted Linked List.	Link
7	Remove Duplicates in a Un-sorted Linked List	Link
8	Write a Program to Move the last element to Front in a Linked List.	Link
9	Add “1” to a number represented as a Linked List.	Link
10	Add two numbers represented by linked lists.	Link
11	Intersection of two Sorted Linked List.	Link
12	Intersection Point of two Linked Lists.	Link
13	Merge Sort For Linked lists.[Very Important]	Link
14	Find the middle Element of a linked list.	Link
15	Check if a linked list is a circular linked list.	Link
16	Split a Circular linked list into two halves.	Link
17	Write a Program to check whether the Singly Linked list is a palindrome or not.	Link
18	Deletion from a Circular Linked List.	Link
19	Reverse a Doubly Linked list.	Link
20	Find pairs with a given sum in a DLL.	Link
21	Count triplets in a sorted DLL whose sum is equal to given value “X”.	Link
22	Sort a “k”sorted Doubly Linked list.[Very IMP]	Link
23	Rotate DoublyLinked list by N nodes.	Link
24	Rotate a Doubly Linked list in group of Given Size.[Very IMP]	Link
25	Flatten a Linked List	Link
26	Sort a LL of 0's, 1's and 2's	Link
27	Clone a linked list with next and random pointer	Link
28	Merge K sorted Linked list	Link
29	Multiply 2 no. represented by LL	Link
30	Delete nodes which have a greater value on right side	Link
31	Segregate even and odd nodes in a Linked List	Link
32	Program for n’th node from the end of a Linked List	Link