Given a linked list consisting of L nodes and given a number N. The task is to find the Nth node from the end of the linked list.

Example: Input: N = 2 LinkedList: 1->2->3->4->5->6->7->8->9

Output: 8

Explanation: In the first example, there are 9 nodes in linked list and we need to find 2nd node from end. 2nd node from end os 8.

Your Task: The task is to complete the function getNthFromLast() which takes two arguments: reference to head and N and you need to return Nth from the end or -1 in case node doesn't exist..

Note: Try to solve in single traversal.

Suppose you have a string, S, made up of only 'a's and 'b's. Write a recursive function that checks if the string was generated using the following rules:

a. The string begins with an 'a' b. Each 'a' is followed by nothing or an 'a' or "bb" c. Each "bb" is followed by nothing or an 'a'

If all the rules are followed by the given string, return true otherwise return false.

Input format : String S Output format : 'true' or 'false'

Constraints : 1 <= |S| <= 1000 where |S| represents length of string S.

Sample Input 1 : abb Sample Output 1 : true

Sample Input 2 : abababa Sample Output 2 : false

Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,2,4,5,6,7] might become:

[4,5,6,7,0,1,2] if it was rotated 4 times. [0,1,2,4,5,6,7] if it was rotated 7 times. Notice that rotating an array [a[0], a[1], a[2], ..., a[n-1]] 1 time results in the array [a[n-1], a[0], a[1], a[2], ..., a[n-2]].

Given the sorted rotated array nums of unique elements, return the minimum element of this array.

You must write an algorithm that runs in O(log n) time.

Example 1:
Input: nums = [3,4,5,1,2]
Output: 1
Explanation: The original array was [1,2,3,4,5] rotated 3 times.

Example 2:
Input: nums = [4,5,6,7,0,1,2]
Output: 0
Explanation: The original array was [0,1,2,4,5,6,7] and it was rotated 4 times.

Implement the class for Max Priority Queue which includes following functions -

1. getSize - Return the size of priority queue i.e. number of elements present in the priority queue.
2. isEmpty - Check if priority queue is empty or not. Return true or false accordingly.
3. insert - Given an element, insert that element in the priority queue at the correct position.
4. getMax - Return the maximum element present in the priority queue without deleting. Return -Infinity if priority queue is empty.
5. removeMax - Delete and return the maximum element present in the priority queue. Return -Infinity if priority queue is empty.

Issues related to DSA, CP, JS, HTML+CSS, operating system

Start with 6 Issues per DSA - 2x{Easy, Medium, Hard} :

• Arrays
• Stacks
• Queues & priority queue
• Linked List
• Hashmap
• Trees
• Recursion
• Dynamic Programming
• Graphs
• General algorithm

The Most Recently Used (MRU) cache is like Cache and LRUCache but uses a most-recently-used replacement policy.

O/P:

Cache after put(1,1) is 1
Cache after put(2,2) is 1 -> 2
Cache after put(3,3) is 1 -> 2 -> 3
Cache after put(4,4) is 1 -> 2 -> 3 -> 4
Cache after put(5,5) is 1 -> 2 -> 3 -> 4 -> 5
Cache after put(6,6) is 1 -> 2 -> 3 -> 4 -> 6
Cache after get(2) is   1 -> 3 -> 4 -> 6 -> 2
Cache after put(7,7) is 1 -> 3 -> 4 -> 6 -> 7

Given a list of n words and a pattern p that we want to search. Check if the pattern p is present the given words or not. Return true if the pattern is present and false otherwise.

Input Format : The first line of input contains an integer, that denotes the value of n. The following line contains n space separated words. The following line contains a string, that denotes the value of the pattern p.

Output Format : The first and only line of output contains true if the pattern is present and false otherwise.

Implement Using Tries Data Structure.

Sample Input:
4
abc def ghi cba
de

Sample Output:
true

Write a JavaScript program to generate the Christmas Tree pattern below. The tree should be composed of zeroes (0), and it must be topped with an asterisk (*).

You are given a string num, representing a large integer. Return the largest-valued odd integer (as a string) that is a non-empty substring of num, or an empty string "" if no odd integer exists.

A substring is a contiguous sequence of characters within a string.

Sample Test Case 1:

Input: num = "52" Output: "5" Explanation: The only non-empty substrings are "5", "2", and "52". "5" is the only odd number.

Sample Test Case 2:

Input: num = "4206" Output: "" Explanation: There are no odd numbers in "4206".

Given two binary strings that represent value of two integers, find the product of two strings. Strings can be very large. So it can go of range of an integer. So you can represent your answer as a modulus of 1e9+7 (i.e. ans = ans%(1e9+7))

Sample Test Case:

str1 = "1100" str2 = "1010" ans = 120

Try to write an efficient solution

Given weights and values of n items, put these items in a knapsack of capacity W to get the maximum total value in the knapsack. In other words, given two integer arrays val[0..n-1] and wt[0..n-1] which represent values and weights associated with n items respectively. Also given an integer W which represents knapsack capacity, find out the maximum value subset of val[] such that sum of the weights of this subset is smaller than or equal to W. You cannot break an item, either pick the complete item or don’t pick it (0-1 property).

You can add assignments in the following directory: PEC-Course -> BranchName -> CourseName & CourseCode -> Year -> assignmentFile

A sample directory structure should look like PEC-Course -> CSE -> computer_graphics_CSN304 -> 2022-> Assignment1

• Create a Cloud Folder/ Add to it if already exists
• Differrent resources for learning cloud technologies eg: AWS, Firebase, Azure
• Link to Sample Cloud Apps and even tutorials

You can get the template from other folders

Mr Chaggan Lal has just learned the maximum subarray sum problem. And while thinking about the solution, he came up with a new problem, the maximum frequent subarray sum problem.

In this problem, you will be given an array A of N integers. You have to choose a non-empty subarray with the maximum possible score. The score of a subarray is calculated as

score(l,r)=(Al+⋯+Ar)⋅(occurrences)

Here, occurrences is the number of occurrences of that subarray in A.

Now Chaggan can't solve this problem as he is aged, so please help him solve it and in return you will get blessings of Chaggan Lal for a Placement😉

Input

• The first line contains an integer T, the number of test cases. Then the test cases follow.
• The first line of each test case contains an integer n, the size of the array.
• The second line contains n integers A1,…,AN.

Output

• For each test case, output the maximum possible score in a new line.

Sample Input 2 6 10 8 -20 5 5 5 10 -5 1 7 -1 2 -4 10 0 -11 3

Sample Output 20 15

Explanation

In the first test case, the maximum score is attained by subarray [5,5], its score is (5+5)⋅2=20 since it occurs twice in A.

In the second test case, the maximum score is attained by both subarrays [1,7,−1,2,−4,10] and [1,7,−1,2,−4,10,0]. Both have sum 15 and occur once, so their scores are 15⋅1=15.

Resources related to:

• Previous year papers for subjects
• Language - how you learned a particular language and the resources you used
• Different Tech resources for appropriate folders
• New Issues are also welcome