Array Algorithms
11. Assume you have an existing array of boolean values named flags. Also assume you have two variables posA and posB. Write a few lines of code that will swap the contents of the array at position A and position B (positions posA and posB). Note: Technically, flags is a variable holding a reference to the array, but for these problems, this detail doesn't matter. Also, I chose boolean values to make sure students could ignore this (not be confused by boolean). Swapping values in an array works the same way with integers, booleans, or even object references.
12. Assume you have an existing array of strings (but with no nulls) named names. Write a few lines of code that will figure out the length of the longest string in the array. When your code is done, place the length of the longest string in a variable named longest. Declare any variables you use (including longest), but assume names has already been declared and populated.
Caution: A deduction will be made if your optimization loop does not use the correct first guess (Never initialize the optimization guess with a constant, even in a situation like this.)
13. Challenge: Repeat the previous problem, but assume there are a few null values in the array (and at least one non-null String). This would be too tough for the exam, but is good practice.
14. Assume you have an existing array of doubles named weightEstimates. The task is to copy the array, but make the copy an array of integers (truncate the values). Write a few lines of code that will copy the double array weightEstimates into a new array named weights. (As with the previous problem, declare any variables you use except weightEstimates.)
15. Assume you have an existing array of integers named temperatures. Some locations in the array have a positive number followed by a negative number: ..., 12, -4, -... Write a few lines of code that counts how many times in temperatures a positive number is followed by a negative number. Put the result in a variable named coldFrontCount. (Again, declare any variables you use.)
16. Write a small bit of code that counts how many nulls are in an array. (Choose your own names/types, but assume your array is already set up.)
