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Given the following tree traversal methods: Pre-order: Visit the root first, then recursively visit all subtrees. In-order (binary tree):  Visit the Left subtree, root, then the right subtree. Post-order: Recursively visit all subtrees, then visit the root.  For each of the following scenarios, select the most appropriate tree traversal method to achieve the desired outcome: A binary search tree stores player scores in its nodes. You want to display scores in ascending order. [a] A tree represents a file system hierarchy. You want to display the file system structure starting from the root, including all  subdirectories and files, mirroring the natural hierarchical listing and exploration of files. [b] A tree represents a file system hierarchy. You want to calculate the total size of a directory, including its subdirectories and files. [c] In Java, garbage collection automatically reclaims memory occupied by objects that are no longer referenced. A tree is used to manage object references, where each node represents an object, and each object can reference other objects. You want to safely delete an object along with all objects it references. [d]     

The Penn Vet Working Dog center maintains a growing database of registered working dogs. Each dog has a unique name made up of lowercase English letters (‘a’ to ‘z’). To support fast lookup and name-based querying, they use a Trie data structure to store all the dog names.  The system supports the following operations: 1. Insert a new dog name into the Trie. 2. Check whether a dog name is already registered. 3. Find all registered dog names that begin with a given prefix. Assume there are n unique dog names in the database, and each name has a length between 1 and m. Answer the following using Big-O notation: a. What is the maximum depth of the Trie? [depth] b. What is the worst-case time complexity for checking if a dog name exists in the Trie? [time] c. What is the worst-case time complexity of retrieving all dog names that start with a given prefix of length  k, assuming there are r such names and the average length of the r retrieved dog names is l? [autocomplete-time]

Consider the code below which aims to find the minimum difference between any two elements in the input array: public int minDiffBetweenElements(int[] arr) {    PriorityQueue minHeap = new PriorityQueue();    for(int i = 0; i < arr.length; i++) {        for(int j = i+1; j < arr.length; j++) {            int diff = Math.abs(arr[i] - arr[j]);            minHeap.add(diff);        }    }    return minHeap.peek();} What is the asymptotic complexity of this method? Select the best answer.

To treat sucking one’s thumb,  one can paint a patient’s fingers with a nasty-tasting nail polish. This procedure best illustrates

Sam often eats large amounts of food in a short period of time, feeling out of control while doing so. Afterward, she secretly forces herself to vomit and sometimes uses laxatives to prevent weight gain. She is deeply concerned about her body shape and weight. Samantha is most likely experiencing symptoms of:

In the Marvel show Moon Knight Marc frequently experiences blackouts and wakes up in unfamiliar places with no memory of what happened. He sometimes speaks and behaves as entirely different people, including a British man named Steven and a ruthless vigilante named Jake. Marc’s symptoms are most consistent with:

Too much ________________ impacts possible onset of schizophrenia. 

Which of the following molecules will show resonating Lewis structures?

What quantity in moles of NaI are there in 175.0 mL of 0.230 M NaI?

If 0.150 moles of NaCl are dissolved in a 250.0 mL solution, what is the concentration of the NaCl solution?