An Algorithmic Approach to Swift Programming

Explore generics in Swift by implementing a swap function using a generic type T to handle ints, strings, and arrays. See how generics reduce duplication.

Build a generic max function for comparable values and constrain with Comparable. Test with ints, strings, and pairs to see lexicographic order in Swift generics.

Explore implementing a generic stack using a struct, with push and pop operations and mutating methods, and compare to a class to highlight value vs reference semantics.

Explore generic structs with multiple parameters in Swift by building an additive dictionary with comparable keys and additive values, including optional returns.

Define a Swift function trapezoid in a playground to compute the circumference, mid-segment, and height from the given side lengths ab, bc, cd, da and area.

Implement a function to check if a string represents a number divisible by a nonzero integer, returning false for invalid input and using guard let for safe conversion.

Explore multiple Swift implementations to check if a number is divisible by n, including an optional version with guard let, modulo checks, and clear handling of nil and zero.

Create a function named strangeRepeat in Swift that splits text into odd and even indexed characters, concatenates odd first then even, and repeats the result copies times.

Validate inputs for reverseSplit in Swift: require q nonnegative and name nonempty with q less than name length; split at q, reverse substrings, and return them with space or nil.

Learn to implement a Swift hello function that takes a non-empty name, returns 'Hello <Name>!' with the name capitalized, or nil for empty input, and explore unit testing.

Organize a SwiftUI project by creating algorithms and views folders, renaming content view to main view, and building a form inside a navigation stack with a navigation title and links.

Create a Hello view with a vertical stack, text, and a bottom text field to practice state-driven UI, then extend with navigation and view builders for future complexity.

Create a reusable SwiftUI card view with a gradient background and a view with help wrapper. Learn to use binding isPresented, information data, and a generic content view via ViewBuilder.

Build a SwiftUI view with help using a state variable and binding. Toggle a pop-up, blur the background, and show a help card with a toolbar.

Begin building a trapezoid view in SwiftUI by composing stacks, four sliders, and a canvas to compute and render a trapezoid path with padding and a blue, clipped background.

Set up trapezoid data in Swift by declaring state variables, computing top, bottom, and height, defining points A–D, implementing a distance function, and assembling circumference, midsegment, height, and area.

Explore building a trapezoid view in SwiftUI, wiring data with stacks, applying sliders to adjust top, bottom, and height, and debugging geometry with square roots.

Draw a trapezoid on the canvas by computing width and height, defining corners, stroking or filling with orange; bind top, bottom, height sliders to shape and bound its area.

Build a SwiftUI view that checks if a user-entered number is divisible by n, displaying a result message and emoji, with a slider to adjust n.

Explore building SwiftUI views for strange repeat and reverse split, using state, computed properties, and a slider to drive dynamic text and name-based messaging.

Create and run your first Swift unit test using XCTest, testing the hello function with assertions for hello run and hello world, and exploring test failures and doubles.

Explore implementing trapezoid tests in Swift, using constants and doubles, and address floating-point equality with an accuracy threshold to validate circumference, height, and mid-segment.

Learn a Swift unit test for number divisibility by n, returning an optional boolean. It trims whitespace and uses named tuples to drive test data.

Explore unit tests for Swift functions strangeRepeat and reverseSplit, examining signatures and optional outputs, with test data and edge cases like negative copies.

Develop a first divisible algorithm to return the index of the first array element divisible by a. Implement tests and SwiftUI views to interactively explore the list, divisor, and results.

Build your first divisible view in swiftui by managing a list and a divisor with a bound slider, while handling optionals and wiring a ticked slider UI.

Explore building a SwiftUI view that adds and removes list elements with plus and minus buttons, and highlight the first divisible index using color, bold text, and a number field.

Implement a generic first divisible function in Swift by using a type parameter T that conforms to the binary integer protocol, replacing int with T and ensuring indices remain integers.

Explore computing the number of strings strictly longer than the average length and the average length itself, returning a pair, implemented with for and while loops, with edge cases.

Calculate the average string length in a list with for and while loops. Handle empty lists, type casting to double, and count strings above the average, all in Swift.

Explore implementing a while loop version for counting string lengths in a list, computing the average, and validating loop control with readability-focused local constants.

Design a SwiftUI view that computes the number of strings above average length from random animal and fruit collections, using optional averages and a reusable random element function.

Build a SwiftUI view with a vstack and form to display a list of items, highlight above-average length items, handle optional averages, and add plus–minus controls for random updates.

Compute the sum of products of consecutive integers in a list, returning the numeric result and a string representation of the computation; handle empty and single-element lists.

Implement a sum of products algorithm in Swift, building a view that computes products from lists, manages lengths, string representations, negative values, and trailing plus signs.

Explore how to implement a sum of products view in Swift using a private list of integers, computed sums, and a form-driven interface with list updates and animations.

Explore creating a subsequence from a list of positive integers where the absolute differences between consecutive elements strictly increase, implemented in Swift with a growing differences function and SwiftUI view.

Develop the growing differences view that takes a random list of integers, computes absolute differences with the previous delta, and appends to a new list when the delta grows.

Explain solving the repeated substring problem: given a string and k, return the first k-length substring with case-sensitive identical characters, along with its starting index, or nil if none.

Apply a Swift loop to slide a window of size k across the string, build a repeat string from the current character, and return the matched substring with its index.

Constructs a SwiftUI repeated substring view for the part two loops and arrays lesson, using state variables, a text field and a slider to determine multiples and display repeats.

Diagnose an off-by-one bug in a repeated substring function, adjust K to K minus one, and verify three C's produce the correct repeat by aligning start, end, and zero-based indexing.

Explore implementing and testing a first divisible function in Swift, returning the index of the first element divisible by a with robust unit tests and edge-case handling.

Develop tests for loops and arrays in Swift, validating number of strings above average with optional averages and accuracy. Explore tests for sum of products, differences, and repeated substring.

Explore functional Swift solutions for first divisible problem, using filter and map on a list of positive integers and returning nil when none exists, and compare readability with imperative approaches.

Explore a functional Swift approach to counting strings above average length, including empty-list handling, computing a double-precision average with reduce, and filtering to count above-average strings.

Apply a functional approach to compute the sum of products of consecutive pairs in a list, handling empty and single-number cases with string representation via map and reduce in Swift.

Explore a Swifty, near functional approach to growing differences by replacing a for loop with forEach and comparing it to the original.

Explore a functional approach to finding repeated substrings in Swift, using sets, map, and compactMap to locate start indices and substrings, while noting efficiency and readability trade-offs.

Implement a Swift function most popular character in a string using a dictionary to count letter frequency, returning the most frequent letter and breaking ties by smaller ascii value.

Explore counting characters with a dictionary to find the most frequent character and return an optional result, and resolve ties by the lowest ascii value, with unit tests first.

Explore unit testing strategies in Swift by validating the most popular character from input text, using nil handling, expected values, and max count concepts.

Learn a Swifty, functional approach to counting character frequencies using reduce and an empty dictionary. Refactor with higher-order functions and shorthand parameters to produce a clean, efficient character counts solution.

Represent sparse matrices with a dictionary that maps index pairs to nonzero values. Compute the difference between two matrices, even with unknown dimensions.

Learn to implement sparse matrices in Swift using a dictionary keyed by hashable pairs with double values, support custom string representations, and subtract matrices while keeping zero elements unrepresented.

Explore test-driven development for sparse matrix subtraction by defining tests first, organizing data structures, and validating expected results with concrete examples.

Implement the difference of two sparse matrices by computing A minus B and storing only non-zero results in M, using B prime for subtraction, and verify with unit tests.

Explore the find substring locations problem by mapping each length k substring to its offsets list. Implement in imperative and functional styles, with tests noting offset order.

Learn to implement a Swift function that finds substring locations and validate it with unit tests, including edge cases like empty strings and when k is large.

Explore a functional approach to finding substring locations in Swift using higher-order functions and reduce, while managing string indices and off-by-one concerns, and weighing readability against brevity with tests.

Build a SwiftUI dictionary UI with a most popular character view that accepts user input, computes the most frequent character, and displays results through a navigable, styled interface.

The sparse matrix is a type alias. It adds a get value function that takes two integers and returns the value or zero if absent.

Explore building a SwiftUI sparse matrix viewer with MxN grid, colorized cells, editable inputs, and a matrix difference view comparing A and B, backed by unit tests.

Demonstrates computing all substrings of a given length k and showing their offsets in a SwiftUI view, with a slider and text input to update the string.

Develop a recursive reverse string function that takes a string and returns it reversed, with a stop condition, without using built-in reverse, while unit tests illustrate the concept.

Explore recursive reverse string solutions and alternative implementations in Swift, using character arrays, inout helpers, and tests to verify even and odd length cases.

Learn to implement a recursive find max function for a list of integers, returning nil for an empty list, without using the built-in max, and validate it with tests.

Explore building a Swift isPalindrome function, handle empty and non-empty inputs, and use recursion to compare first and last characters with tests for even and odd cases.

Apply a recursive climb combinations approach to count the ways to climb n steps with 1 or 2 steps, using base cases n=1 and n=2, and note n=10 yields 89.

Develop unit tests for the recursive climb combinations algorithm, exploring n values from zero to ten with inputs like one and two steps, and compare against expected sequence counts.

Implement a climb combinations function that follows a Fibonacci-like pattern for ways to climb n steps, with base cases for n up to two and negative input returning zero.

Build the sample UI for reverse strings, max value display with random numbers and a smiley, and stair-climb demonstrations, while toggling between description and functional displays to clarify UI concepts.

Develop recursion in swiftui by building a recursion view and multiple subviews—reverse string, find max, palindrome, and climb combinations—and wiring them to a running app with tests.

Build a reverse string view in SwiftUI that reverses text once or twice, using state variables, computed properties, bindings, and animated transitions.

Implement a SwiftUI find max view that computes a max from a list of integers, highlights the max with red text and large title, and updates the list with animation.

Create a palindrome view in SwiftUI by managing input state, checking for palindrome text, and displaying animated messages; generate random palindromes with a button and a computed property.

Explore a SwiftUI climb combinations view that toggles between short and long descriptions using a message function, with a clean, readable layout in a VStack and list.

Implement the four-bonacci sequence in Swift, compare a recursive version without memoization to a memoized version, and observe runtime improvements.

Explore a four-bonacci recursive implementation in Swift, with base cases and four prior terms, focusing on readability and correctness. Build unit tests to evaluate memoization and performance.

Implement a four-bonacci memoization solution that uses a mutable dictionary to store computed values, initializes base cases, and uses a memoized helper to sum the four prior values, avoiding recursion.

Explore a four-bonacci memoization approach in Swift, implementing four-queue memo helpers, comparing versions, debugging indices, and addressing arithmetic overflow with large inputs.

Implement four-bonacci memoization in Swift using a big int package, refactor with a BigInt type alias, and validate via tests and compile checks.

Assess four-bonacci performance by comparing recursive and memoized implementations, capture baseline times, and highlight memoization's speedup for large inputs, including big integer handling.

Explore the factorial problem by implementing both recursive and non-recursive solutions with memoization, using big integers and tests for nonnegative n.

Explore a recursive factorial implementation in swift, using a big integer type, with unit tests and a performance comparison to memoization, highlighting test data and execution results.

The lecture shows memoized factorial using a memo dictionary and helper function, tests the implementation, and finds memoization offers no gain due to factorial's lack of branching.

Learn how to implement a memoized power function using a test-driven development approach in Swift, exploring a memo dictionary and a hashable key to optimize recursion.

Refine power memoization by using a base-exponent key and memoized results for exponent minus one. Update to big integer outputs and perform a clean build with tests.

Use memoization to calculate the binomial coefficient with a recursive recurrence, define binomial(n, k) returning a big integer, and apply base cases and a memo table related to Pascal's triangle.

Create memoization views for Bonacci, factorial, power, and binomial views within a SwiftUI app, wiring up a memoization view, individual views, and navigation to demonstrate recursion.

Create a SwiftUI fibonacci view using a big integer implementation, showing numbers in a scroll view with centered, multi-line text, configurable max and skip line, and padding for layout.

Implement the factorial view by reusing the memoized factorial code, cap at 100, and verify the app displays the factorial. Explore upcoming topics: power and binomial coefficients.

Implement a power view in SwiftUI by adjusting base and exponent with sliders, displaying a big integer result, and exploring layout options like VStack, min scale factor, and scroll view.

Improve the power view by rendering exponents with Unicode superscripts using a digit dictionary, exponent array, and an HStack, while gracefully handling optionals with nil coalescing and avoiding force unwrapping.

Create a SwiftUI binomial view that computes the binomial coefficient from N and K with sliders. Use symmetry k = min(K, N-K) to speed calculations for N up to 1000.

Explore classes versus structs by building a hotel model with minibar, price list, and price as classes, including a dictionary for items and custom string representations.

Learn to complete the minibar class by implementing drink and snack handling, refactoring into a private function that consumes products, updating price lists, and validating with tests.

Implement and test a minibar with drinks and snacks, using a price list for items like Coke, rum, M&Ms, and cake, and display the bill.

Define a room class for a hotel with attributes minibar, floor, room number, guests, cleanliness, a rank enum, and a default satisfaction of 1.0 plus an initializer.

Explore implementing a Swift room class in part 2, covering occupied and empty checks, cleanliness and rank-based tiebreakers with floor, check-in/out, moving guests, and a descriptive room report.

Implement a room move in Swift with an in-out parameter that guards moves when the source is empty or the destination is occupied, transfers guests, and caps satisfaction at 5.0.

Convert containsGuest into a computed property on the room class, conform to the custom string convertible protocol, and test case-insensitive containment of guests as you move them between rooms.

Convert the room class to a computed description and conform to custom string convertible. Build a descriptive string including floor, room, guests, cleanliness, and rank name, then test outputs.

Implement a hotel class with name and rooms, compute occupancy and room counts, and provide check in, check out, and upgrade methods handling ranking, availability, and case-insensitive guest lookup.

Explore a hotel class checkout by iterating rooms, checking for a guest, performing checkout, and returning the occupied room or nil if none found, with a preview to upgrade next.

Define a hotel class in Swift with name and rooms, implement an initializer, add a computed rooms-occupancy property, and conform to CustomStringConvertible for check in, check out, and upgrade features.

Follow the upgrade logic across hotel rooms by moving guests to a better empty room. Check in and check out guests accordingly, prioritizing readability over efficiency in the upgrade implementation.

Demonstrates implementing hotel check-in by iterating through rooms, finding an empty room whose rank equals the guest's desired rank, and returning the room or nil if unavailable.

Craft a hotel description generator in Swift that computes total rooms and occupied rooms, applies pluralization rules, and builds a readable description via string interpolation.

Implement and test a Swift hotel model that manages rooms, occupancy, check-in and check-out, and upgrade outcomes with descriptive output.

Explore a Swift implementation of a generic doubly linked list node with optional previous and next pointers, an initializer, and bidirectional operations like search, insert, and remove.

Explore building a generic doubly linked list in Swift, including init and append operations, head and tail management, and node linking with previous and next pointers.

Design a SwiftUI node view with a generic value and selectable state, featuring animated tap to toggle, color cues, a rounded border, and examples linking nodes in the next lecture.

Create a null view that displays the word null in bold blue headline font, padded and overlaid with a stroked rounded rectangle, before building the doubly linked list view.

Implement a SwiftUI doubly linked list view for a generic type T, render nodes horizontally with arrows, expose a get node values function, and enable identifiable conformance for seamless previews.

Conform the doubly linked list and its node to equatable, implement delete by updating previous and next pointers, and validate behavior with unit tests such as removing 2 from 2,3,5.