1Multidimensional Arrays10/17/20072Opening Discussion■Let's look at some solutions to the interclass problem.■Do you have any questions about the assignment?■ACM's “Make the Most of Your Major” event is this evening.■Fun things in planetary science.Lots of Cassini data on rings and moons.Nice model of planetary formation.3Searching■Far more common than sorting is the act of searching.■If I give you an array of ints and ask you to tell me where the number 33 is, what would you do?■How fast is this procedure? How many checks do you need to do?4Binary Search■The real benefit of sorting is that we can search faster. If data is sorted we can do a binary search.■Start in the middle and determine if what you are looking for is on the right or the left.■This only works for sorted data, but it is MUCH faster for big data sets. It is O(log2 n) instead of O(n).5Array Types■When we declare int a[] you can think of it as a being of type int[]. (That is actually the accepted syntax in Java.)■The array types are themselves types. By adding the brackets you basically create a new type that is an array of the base type. You can do this with any type.6Multidimensional Arrays■If array types are types and we can make arrays of any type then we can make arrays of arrays.■This is what produces multidimensional arrays. To declare a multidimensional array simply put multiple sets of brackets with sizes after the variable name.int a[10][20];■When you pass a multidimensional array, you must specify the size of every dimension except the first one.■You can put lots of dimensions on an array, but there are few applications needed more than three. Memory requirements grow quickly.7Mazes■There are lots of different uses for 2-D arrays, but one of my favorite is that of mazes.■These also provide a great playground for recursion because maze functions are among the set that are hard to write with loops, but easy to do with recursion.8Minute Essay■Given that an int takes four bytes on these machines, how much memory would the following declaration consume?int a[10][5][20][100];■Remember that the assignment is due on Friday.■ACM's “Make the Most of Your Major” event is this evening at 7pm in HAS 340.■Interclass Problem – Write a function that tells you the length of the longest path from a given location to 0,0 on a maze made with a 2-D array of
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