Notes, summaries, assignments, exams, and problems for Computer science

Conditional Control Structures

Conditional control structures dictate the flow of execution by allowing specific blocks of code to run only when certain conditions are met.

1. The If Statement

The If statement executes a block of code only if the specified condition evaluates to true. Otherwise, the block is skipped entirely.

Syntax:

if (condition) {
    // statements (If Block)
}
// other statements

Note: A flow chart typically illustrates the execution path based on the condition.

2. The If-Else Statement

If the condition is true, the If block is executed. If the condition is false, the alternative Else block is executed.

Syntax:

if (condition) {
    // statements (If Block)
} else {
    // statements (Else Block)
}

3. The Else-If Ladder Statement

The...

Tokens

In programming, a token is the smallest meaningful element in code. They are the building blocks of a language's syntax. Common token types include:

• Keywords: Reserved words like if, else, while, and int (for declaring integers).
• Identifiers: Names given to elements like variables (e.g., sum), functions, and arrays.
• Constants: Unchanging values during program execution (e.g., 3.14 for pi).
• Operators: Symbols for mathematical or logical operations (e.g., + for addition).
• Separators: Punctuation like commas (,), semicolons (;), and braces ({}).

Example: int sum = 10 + 5;

In this line, int is a keyword, sum is an identifier, = is an operator, 10 and 5 are constants, and ; is a separator.

Arithmetic Operators

C has nine arithmetic operators for basic...

Implementing Boolean Functions with Truth Tables

Problem 1: Implement the following function F(A, B, C) = Σ(2, 5, 6, 7) using a truth table with:

• a. Decoder
• b. Multiplexer

Truth Table for Function F(A, B, C)

a. Decoder Implementation

A decoder is used to select one of the outputs based on the input combination. In this case, we have 3 inputs (A, B, C) and 8 possible combinations. The truth table shows that F = 1 for input combinations (010), (101), (110), and (111), and F = 0 for all other combinations. To implement this, we connect the corresponding decoder outputs to an OR gate.

b. Multiplexer Implementation

A multiplexer (MUX) selects one of the input lines and passes it to the output. The selection is controlled...

Lecture 2: Dynamic Dispatch and Interfaces

• Dynamic Dispatch: The process of selecting which implementation of a polymorphic operation to call at runtime.
• Interface: Calling a method that is not in the interface will cause a compilation error.

Lecture 3: N/A

Lecture 4: Method Contracts, Exceptions, and Unit Testing

• Method Contract: Should define pre/post conditions and exceptional behavior. The client is to blame if the precondition is not met, and the service is to blame if the postcondition is not met. Exceptional behavior specifies what the code will do if a precondition is violated.
• Exception: Runtime exception (unchecked) and IO exception (checked). The IO exception must be caught; otherwise, the code won't compile.
• Unit Test: Test boundary

Arithmetic Operations in Java

Input Form

<% String num1Str = request.getParameter("num1"); String num2Str = request.getParameter("num2"); String operation = request.getParameter("operation"); if (num1Str != null && num2Str != null && !num1Str.isEmpty() && !num2Str.isEmpty() && operation != null) { double num1 = Double.parseDouble(num1Str); double num2 = Double.parseDouble(num2Str); double result = 0; switch (operation) { case "add": result = num1 + num2; out.println("

Result: " + result + "

"); break; case "subtract": result = num1 - num2; out.println("

Result: " + result + "

"); break; case "multiply": result = num1 * num2; out.println("...

Core Graphic Design Concepts and Terminology

Vector Graphics and File Types

• Vector allows for resizing without loss in quality.
• Vector graphics are smaller in file size.

• PNG file type (Portable Network Graphics).
• SVG (Scalable Vector Graphics).

Digital Asset Sourcing

• He found the images online, but they were in the public domain.
• The team member created the images himself.

The whole is greater than the sum of the parts.

Typography and Text Handling

• Kerning: The spacing between specific pairs of characters.
• Leading: The distance between each line of text.

Font Classifications

• Script
• Decorative
• Serif
• Sans Serif

Text Overflow

Even though it's not visible, the excess text is still in the bounding area, and a small plus (+) symbol is displayed at the bottom of the...

Bit stuffing and destuffing are crucial techniques used in data link layer protocols to ensure reliable data transmission. They prevent sequences of data bits from being misinterpreted as control characters or flags, especially when the data itself contains patterns identical to these control sequences.

What is Bit Stuffing?

Bit stuffing is the process of adding one or more extra bits into a data stream to break up a sequence of identical bits that might otherwise be misinterpreted as a control signal. For example, in protocols like HDLC, a flag sequence (01111110) is used to mark the beginning and end of a frame. To prevent the actual data from containing this sequence, a '0' bit is stuffed after every five consecutive '1's in the data stream....

C++ Loops: While, Do-While, and For

While Loop Format

while (condition)
{
    statements(s);
}

How While Loop Works

If the condition is true, the statement(s) are evaluated again. If false, the loop is exited.

While Loop Example

int val = 5;
while (val >= 0)
{
    cout << val << " ";
    val = val - 1;
}

A while loop is a pretest loop (the condition is evaluated before the loop executes).

• If the condition is initially false, the statement(s) in the body of the loop are never executed.
• If the condition is initially true, the statement(s) in the body will continue to be executed until the condition becomes false.

The loop must contain code to allow the condition to eventually become false so the loop can be exited. Otherwise, you have...