AlphaSense Automation Test Engineer Interview Questions and Answers for Freshers

Find an odd occurring number among even occurring numbers.

• Use XOR operation to cancel out even occurring numbers and get the odd occurring number.

• Iterate through the array and XOR each element with the result variable.

• The final result will be the odd occurring number.

Print the spiral order of a binary tree and matrix.

• For binary tree, use level order traversal and alternate direction for each level.

• For matrix, use four pointers to traverse in spiral order.

• Example for binary tree: 1 -> 2 -> 3 -> 4 -> 5 -> 6 -> 7 -> 8 -> 9

• Example for matrix: 1 2 3 4 -> 8 7 6 5 -> 9 10 11 12 -> 16 15 14 13

Finding pairs in an array with a given sum.

• Iterate through the array and for each element, check if the difference between the given sum and the element exists in the array.

• Use a hash table to store the elements of the array and their indices for faster lookup.

• If there are multiple pairs with the same sum, return any one of them.

• If no pair is found, return null or an empty array.

Find total number of k element with given avg in an array in minimum time complexity.

• Use sliding window technique to traverse the array in O(n) time complexity.

• Maintain a sum variable to keep track of the sum of elements in the window.

• If the sum of elements in the window is equal to k times the given avg, increment the count.

• Move the window by subtracting the first element and adding the next element in the array.

Printing non-boundary elements of a binary tree

• Traverse the tree in any order (preorder, inorder, postorder)

• Check if the current node is not a boundary node (not the first or last node in its level)

• If it is not a boundary node, print its value

• Recursively traverse its left and right subtrees

To test if every left child's value is less than the right child's value in a binary tree.

• Traverse the binary tree using any traversal algorithm (e.g., in-order, pre-order, post-order)

• Compare the value of each left child with its right child

• If any left child's value is greater than or equal to its right child's value, return false

• If all left child's values are less than their right child's values, return true

Cloning a linked list-like structure

• Create a new node for each node in the original linked list

• Set the value of the new node to the value of the corresponding node in the original linked list

• Set the next pointer of the new node to the new node corresponding to the next node in the original linked list

• Repeat the above steps until all nodes in the original linked list are cloned

To find the nth character in a stream of bytes, we need to read the stream byte by byte until we reach the nth position.

• Start reading the stream byte by byte until you reach the nth position

• Return the byte at the nth position

• If the stream ends before reaching the nth position, return null or throw an exception

Rearrange a string to avoid consecutive same characters.

• Iterate through the string and keep track of the previous character.

• If the current character is the same as the previous, swap it with the next different character.

• Repeat until no consecutive same characters are left.

The task is to find the next highest palindrome number given a number.

• Convert the given number to a string

• Check if the number is already a palindrome

• If not, increment the number by 1 and check if it is a palindrome

• Repeat the previous step until a palindrome is found

Canonicalizing a directory path involves simplifying and standardizing the path to remove any redundant or unnecessary elements.

• Remove any consecutive slashes and replace them with a single slash

• Remove any trailing slashes

• Resolve any relative paths (e.g., '..' and '.')

• Handle special cases like the root directory ('/')

• Normalize the path by removing any unnecessary elements