10+ Interview Questions and Answers

To reverse the order of words in a given sentence, we need to split the sentence into words and then reverse the order of the resulting array.

• Split the sentence into words using a delimiter like space or comma

• Reverse the resulting array of words

• Join the reversed array of words using a delimiter to form the reversed sentence

Data is fetched through RESTful APIs using Python requests library. Machine learning is used for predictive analysis.

• API data is retrieved using HTTP GET requests

• Python requests library is used to handle API requests and responses

• Data is parsed using JSON library

• Machine learning models are trained on historical data to predict future outcomes

• Scikit-learn library is used for machine learning tasks

Given N people on an M*M grid, find the point with the least total distance for all to meet.

• Calculate the Manhattan distance for each point on the grid

• Find the point with the minimum total distance

• Use dynamic programming to optimize the solution

• Consider edge cases such as when N=1 or M=1

Remove duplicates in unsorted linked list

• Create a hash table to keep track of visited nodes

• Traverse the linked list and check if the node is already visited

• If visited, remove the node from the linked list

• Time complexity: O(n)

• Example: 1 -> 2 -> 3 -> 2 -> 4 -> 1 -> null

• Output: 1 -> 2 -> 3 -> 4 -> null

The number of islands problem involves counting the number of connected islands in a grid.

• An island is a group of connected 1s in a grid of 0s and 1s.

• Use depth-first search or breadth-first search to traverse the grid and count the islands.

• Keep track of visited cells to avoid counting the same island multiple times.

Find intersection point of two linked lists.

• Traverse both lists and find their lengths

• Move the head of the longer list by the difference in lengths

• Traverse both lists in parallel until they meet at the intersection point

Check if there is a path in a binary tree to a given target

• Start from the root node and traverse the tree using depth-first search (DFS)

• Keep track of the current path sum and compare it with the target value

• Return true if a path with the target sum is found, otherwise return false

Scope resolution program is used to determine the scope of a variable in a program.

• It helps in identifying the location of a variable in a program

• It helps in avoiding naming conflicts between variables

• It can be done using the dot operator or the arrow operator in object-oriented programming

• It can also be done using the scope resolution operator (::) in C++

To delete a node from a singly or doubly linked list, update the pointers of the previous and next nodes.

• For a singly linked list, update the next pointer of the previous node to skip the node to be deleted.

• For a doubly linked list, update the next pointer of the previous node and the previous pointer of the next node to skip the node to be deleted.

The depth of a tree is the length of the longest path from the root node to a leaf node.

• The depth of a tree can be calculated by traversing the tree and keeping track of the depth at each node.

• The depth of a tree with only one node (the root) is 0.

• For example, in a binary tree, the depth of the tree is the maximum depth of the left and right subtrees plus 1.

Use regex pattern to validate an email address

• Use regex pattern /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/

• Ensure email has valid format with username, @ symbol, domain, and top-level domain

• Test regex pattern against different email addresses for validation

BFS (Breadth First Search) is a traversal algorithm used to visit all nodes of a tree level by level.

• Start by visiting the root node, then visit all its children before moving on to the next level

• Use a queue data structure to keep track of nodes to visit next

• Repeat the process until all nodes have been visited

Two sum problem involves finding two numbers in an array that add up to a specific target. Water tank problem involves calculating the amount of water that can be trapped between the bars.

• For Two sum problem, use a hashmap to store the difference between the target and each element in the array. Check if the current element exists in the hashmap.

• For Water tank problem, use two pointers approach to calculate the maximum water that can be trapped between the bars.

• Example for Tw...read more

The square root of a number N is a value that, when multiplied by itself, gives N.

• The square root of 9 is 3, because 3 * 3 = 9

• The square root of 16 is 4, because 4 * 4 = 16

• The square root of 25 is 5, because 5 * 5 = 25