Data Analytics Interview Questions and Answers for Freshers

The task is to determine the lexicographically smallest array that can be obtained by performing at most 'K' swaps of consecutive elements.

• Iterate through the array and swap elements to make the array lexicographically smallest.

• Keep track of the number of swaps made and stop when the limit 'K' is reached.

• Use a sorting algorithm to find the lexicographically smallest array after at most 'K' swaps.

The task is to find the total number of ways to make change for a specified value using given denominations.

• Create a dynamic programming table to store the number of ways to make change for each value up to the target value.

• Iterate through each denomination and update the table accordingly.

• The final answer will be the value in the table at the target value.

• Consider edge cases such as when the target value is 0 or when there are no denominations that can make the change.

Given an array and a target sum, find pairs of elements that add up to the target sum.

• Iterate through the array and for each element, check if the complement (target sum - current element) exists in a hash set.

• If the complement exists, add the pair to the result list.

• Sort the result list based on the first element of each pair, and then the second element if the first elements are equal.

Find the minimum time required to rot all fresh oranges in a grid.

• Iterate through the grid to find rotten oranges and their adjacent fresh oranges.

• Use BFS or DFS to simulate the rotting process and track the time taken.

• Return the minimum time taken to rot all fresh oranges or -1 if not possible.

Find the longest common prefix among an array of strings.

• Iterate through the characters of the first string and compare with corresponding characters of other strings.

• Stop when a mismatch is found or when reaching the end of the shortest string.

• Return the prefix found so far as the longest common prefix.

Find the peak element in an array of integers.

• Iterate through the array and check if the current element is greater than its neighbors.

• Handle edge cases where the first or last element can be a peak.

• Return the peak element found.

Evaluate division problem statement with given fractions and values to calculate the value of a given fraction.

• Use a graph data structure to represent the fractions and values.

• Perform depth-first search (DFS) to find the value of the given fraction.

• Multiply the values of the fractions along the path from numerator to denominator to get the final result.