Exercise 9. Describe in plain English an algorithm that computes the number of common elements in 2 arrays of integers. You can assume that there are no duplicates in the first array, and also no duplicates in the second array. For example if array a₁ = [9, 3, 1, 5, 7, 11] and array a2 = [6, 2, 7, 8, 10, 5, 1], the algorithm should return 3 because the two arrays have three numbers in common, namely 1,5,7. Your algorithm should run in O(n log n) time.

Debugging challenge: Consider the code example below. This program is designed to compare the contents of two arrays: if they are equal, the program should display "TRUE," if the arrays are not equal, the program should display "FALSE". However, even when the arrays have the same value, the program always prints "FALSE", regardless of the values in arrays a and b. What is going on here? What about the program causes the comparison to always fail? int a[4] {1, 2, 3, 4}; int b[4] = {1, 2, 3, 4}; if (a == b) { display ("TRUE"); else { display ("FALSE");

Write a program that reads student scores into an array, gets the best score, and then assigns grades based on the following scheme: • Grade is A if score is • Grade is B if score is • Grade is C if score is • Grade is D if score is • Grade is F otherwise. best - 10 best - 20; best - 30; best - 40; The program prompts the user to enter the total number of students, then prompts the user to enter all of the scores, and concludes by displaying the grades

JAVA PROGRAM: Monkey Business A local zoo wants to keep track of how many pounds of food each of its three monkeys eats each day during a typical week. Write a program that stores this information in a two-dimensional 3 × 5 array, where each row represents a different monkey and each column represents a different day of the week. The program should first have the user input the data for each monkey, or use constant values rather than asking user for input. Then it should create a report that includes the following information: Display 3X5 array first. Average amount of food eaten per day by the whole family of The least amount of food eaten during the week by any one The greatest amount of food eaten during the week by any one Input Validation: Do not accept negative numbers for pounds of food eaten.