Verifone Interview Questions, Process, and Tips

Copy a binary tree with a friend node linking to a random node.

• Create a new node for each node in the original tree

• Copy the value of the original node to the new node

• Link the new node to the corresponding node in the new tree

• Generate a random number to select a random node in the new tree

• Link the friend node of each node in the new tree to the randomly selected node

Count the number of connected 1s in a 0/1 matrix.

• Traverse the matrix and for each 1 encountered, perform a depth-first search to find all connected 1s.

• Mark the visited 1s to avoid revisiting them.

• Increment the count of areas for each new group of connected 1s found.

• Return the total count of areas.

• Consider edge cases like empty matrix, matrix with all 0s, or matrix with all 1s.