ISTM 250 EXAM 3 QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026

ISTM 250 EXAM 3 QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026 Methods in Queue() - Answers .____ Enqueue (element) - Specified object to end of queue (puts in back of line) (LIKE ADD IN LISTS) Dequeue () - First object @ front removed from Queue (LIKE REMOVE IN LISTS) Clear() - All items removed from queue Peek() - Retrieves next item in queue, doesn't delete it (looks, good for loops) Arrays & Collections: - Answers Objects that act as "containers:" have to be same value types ARRAY (.NET Class): Group of related variables (can be retrieved) COLLECTIONS: (Classes in the .NET framework), variable in size (unlike arrays), feature of C# Arrays - Answers Class of HOMOGENEOUS DATATYPES (can also work w/ strings) Shortcut from creating separate variables for every user-input. Use elements to combine them into an array. Exist in ALL programming languages! Arrays in excel - Answers Highlight range of cells (indexes) Indexes - Answers Order array elements starting from 0. Array Format (single statement): - Answers type [#] arrayName array = new type [arrayLength]; type = datatype of array "arrayLength" is how many elements you want to add # = elements, each with its own space/size/amount (values in bytes pulled aside and reserved) Instantiating new array - Answers (one line) = new type[length from 0]; Number in length assigns x locations in memory to hold values. Starting Address is the beginning point Default values for array elements - Answers BEFORE ADDING/ASSIGNING VALUES: Numeric = 0 Char = '0' (null character) Boolean = false Date Time = 01/01/0001 00:00:00 Reference = null Length of Array: - Answers SIZE: Amount of elements in the array (starting from 0) Assign array elements their value: - Answers Assignment Statement: Ascending Order: arrayName [index] = value; Trying to assign more elements than the declared array holds. - Answers Index Out of Range Exception Declaring and assigning arrays/collections in one statement: - Answers INITIALIZER: type[] arrayName = {w, x, y, z}; (size infered) Commas help understand amount of elements in array! Array Length Property - Answers arrayName.Length - how many elements in array Length can be used in average equations (array sum of values / array length) Foreach Loop - Answers ACCESS ARRAYS AND COLLECTIONS foreach (type elementName in arrayName) { code; } (best if all elements, only certain use for) Element name random, not established before Array Shapes: - Answers One-dimensional (linear) Rectangular/2D [row, column] Properties of Arrays: - Answers Name.Length (number of elements in all dimensions) Static Method of Arrays: - Answers Methods of Array Class (Array.___) Copy (array, array, length) BinarySearch(array, value) Sort(array) Sort - Answers Sorts 1D array elements in ascending/alphabetic order. (DON'T HAVE TO INSTANTUATE) Array.Sort(NAME); Binary Search - Answers Arrays & Lists (Collections) Searches 1D array that's ALREADY SORTED ASCENDING (applies to both) for an element, returns index. ValueName = Array.BinarySearch(Name, Value); " " = " "[ValueName]; (Negative number if index not found) Copy - Answers CAN'T SET TWO ARRAYS @ EQUAL, will just create new name for memory space. OVERLOADED METHOD: More than one implementation. Beg: Array.Copy(from, to, length/element amount to copy); Can be array.Length to copy all elements to the other Not Beg/Certain Spot: (from, from index, to, to index, length) Methods that accept arrays as arguments to change their elements: - Answers PASSED AS REF BY DEFAULT! private VOID Name(type[] Name) { for(int i = 0; i ArrayName.Length; i++) { ArrayName[i] + code; } ARRAY ARGUMENTS = CHANGING ELEMENTS, NOT RETURNING NEW VALUE Called w/ no "=" sign Types of Collection Classes: - Answers ArrayList - Index to store/access each element (best sequentially, worse at putting elements into middle of list). Queue & Stack - Methods to add/remove elements (MORE limited) Lists above are ONLY c# centric Collection code for list: - Answers List type Name = new Listtype(); List Add Method - Answers Adds values/items to list automatically (has to compile w/ list type) Accessing list elements w/ for loop: - Answers for (int i = 0; i List.Count; i++) { type number = List[i]; } Properties of list: - Answers Capacity - (like length of arrays) Number of elements list can hold, WON'T SET VALUE Count - Elements in list (null values by default, won't count those!) Indexer for lists: - Answers Gets or sets element at the index (starts @ 0). List Methods: - Answers .____ Add(object) - Adds element to the end of the list, returns index Clear() - Removes all elements, count property is 0. Contains(object) - Boolean, if object is present Insert(index, object) - rest of list shifted one place right Remove(object) - FIRST OCCURENCE only, shifts list left RemoveAt(index) BinarySearch(object) - searches list, returns index Sort() - ascending Add elements to list past capacity: - Answers Capacity doubles every time the limit is reached NO capacity set = 4 capacity set by default. Remove ALL of an element in a list - Answers while (List.Contains(element)) - List.Remove(element); Properties of Queue() - Answers Count - number of items in queue Queue - Answers Implements first in, first out method (FIFO) Queuetype nameQueue = new Queuetype(); Stack - Answers Implements last in, first out (LIFO) Stacktype nameStack = new Stacktype(); Properties of Stack() - Answers Count Methods of Stack() - Answers .____ Push (object) - adds onto top of stack Pop() - Top object removed Clear() Peek() DateTime - Answers Datatype, stored as numbers DateTime dtVariableName = new DateTime(4-digit-year, month, day[, hour-sec[, milisecond]]); Can parse/try parse to take string elements and put it into a date time: DateTime dtVariableName = DateTime.Parse ("01/30/2023", etc.) - converts to time