Zscaler Interview Guide

You're given an array of numbers and a target value 'k'. You can apply specific operations to array elements to maximize the array's sum; determine the minimum number of operations needed to make the sum greater than or equal to k.

Find two numbers in an array that form a 'strong pair' (where one number is no more than twice the other). Maximize the XOR result of all possible strong pairs, and return that maximum value.

Rearrange the digits of a given number to form the largest possible number. You can only swap digits with the same parity (even or odd).

Given an array of integers, find the maximum XOR value of a pair of numbers that also satisfy the condition where the smaller number is at least half of the larger number.

Given a date string, determine which day of the year it represents (e.g., January 1st is day 1). Calculate the day number accounting for leap years.

You are given a list of transactions between people. Determine the minimum number of transactions needed to settle all debts, such that everyone owes or is owed exactly zero.

You are given an array of integers. Determine the minimum number of operations needed to sort the array in non-decreasing order, where each operation involves replacing an element with one or more elements that sum to the original value.

You are given a square matrix representing an image. Rotate the image by 90 degrees clockwise in-place.

You are given an array where each element represents your maximum jump length at that position. Determine if you can reach the last index starting from the first index.

Given an array of numbers and a threshold, find the smallest divisor that ensures the sum of the divisions (ceiling) is less than or equal to the threshold. You need to efficiently search for this divisor.

Find the longest string that is a prefix of all strings in a given array. If no common prefix exists, return an empty string.

You're given a sorted array that has been rotated, and a target value. Find the index of the target value in the rotated array, or return -1 if it's not present.

Design a data structure to calculate the moving average of a stream of numbers. The moving average is calculated over a sliding window of a specified size.

Design a data structure that acts as a Least Recently Used (LRU) cache. Implement methods to get and put key-value pairs, evicting the least recently used entry when the cache is full.

Transform one word into another, one letter at a time, using only words from a given dictionary. Find the shortest sequence of words to reach the target.

Find the smallest subarray within a given array that has the same degree as the entire array. The degree is defined as the highest frequency of any element.

A robot follows a sequence of instructions (move and rotate). Determine if the robot ends up back at its starting point, or if it's trapped in a repeating circular path.

Given an array of integers, determine how many triplets sum up to a multiple of a given number. Count the number of such divisible triplets.

You're given an array of numbers. Find the minimum number of increments needed to make all the numbers in the array unique.

Find the length of the longest substring within a given string that contains no repeating characters. The substring must be contiguous.