SDE - 1

You are given an integer array 'A' of size 'N', sorted in non-decreasing order. You are also given an integer 'target'. Your task is to write a function to search for 'target' in the array 'A'. If it exists, return its index in 0-based indexing. If 'target' is not present in the array 'A', return -1.

Note:

You must write an algorithm whose time complexity is O(LogN)

Given a string 'S' of length 'L', return the length of the longest substring without repeating characters.

Example:

Suppose given input is "abacb", then the length of the longest substring without repeating characters will be 3 ("acb").

You are given an array Arr consisting of n integers, you need to find all the distinct triplets present in the array which adds up to zero.

An array is said to have a triplet {arr[i], arr[j], arr[k]} with 0 sum if there exists three indices i, j and k such that i!=j, j!=k and i!=k and arr[i] + arr[j] + arr[k] = 0.

Note :

1. You can return the list of values in any order. For example, if a valid triplet is {1, 2, -3}, then (2, -3, 1), (-3, 2, 1) etc is also valid triplet. Also, the ordering of different triplets can be random i.e if there are more than one valid triplets, you can return them in any order.
2. The elements in the array need not be distinct.
3. If no such triplet is present in the array, then return an empty list, and the output printed for such a test case will be "-1".

For a given a string(str), find and return the highest occurring character.

Example:

Input String: "abcdeapapqarr"
Expected Output: 'a'
Since 'a' has appeared four times in the string which happens to be the highest frequency character, the answer would be 'a'.

If there are two characters in the input string with the same frequency, return the character which comes first.

Consider:

Assume all the characters in the given string to be in lowercase always.

Given a integer array nums of length ‘N’ and an integer ‘K’, return the number of pairs ‘(i, j)’ such that:

1 <= ‘i’ < ‘j’ <= ‘N’ and ‘nums[i] * nums[j]’ is divisible by ‘K’.

EXAMPLE :

‘N’ = 5, ‘K’ = 4, ‘nums’ = [2, 6, 1, 7, 8]
Output: 5
Explanation: (1, 2), (1, 5), (2, 5), (3, 5), and (4, 5) pairs have their products divisible by K.

Which data structure is commonly used to implement back button navigation in applications?

Which data structure is commonly used to implement forward button navigation in applications?

Identify the data structures commonly used to implement both back and forward button navigation in applications, and explain how they work together.

What is the difference between an array and a linked list?

You are tasked with creating "Add to Cart" functionality for an e-commerce application. The cart should store a list of items that a user intends to purchase. Each item must have a unique identifier (such as an ID or SKU), a name, a price, and a quantity. The cart must support various operations, including adding items, updating quantities, removing items, and displaying the current contents of the cart.