CISC 1600/1610 Computer Science I: More Flow of Control Using Boolean Expressions

Short-Circuit Evaluation in C++

• Short-circuit evaluation occurs when evaluating boolean expressions and stops processing as soon as a definitive truth value is determined.
• It optimizes performance by eliminating unnecessary evaluations in boolean expressions.

Boolean Expressions vs. Arithmetic Expressions

• Evaluating boolean expressions is similar to arithmetic expressions in that both follow precedence rules and operational order.
• Both types of expressions can yield true/false or numerical results, respectively.

C++ Boolean Evaluation

• C++ employs short-circuit evaluation to enhance efficiency and avoid potential errors.
• In an 'and' operation (&&), if the first expression evaluates to false, the second expression is not checked since the overall result will be false.

Types of Evaluation

• Complete evaluation checks every expression in a boolean statement, unlike short-circuit evaluation, which may skip some checks.

Advantages of Short-Circuit Evaluation

• It reduces computation time by bypassing unnecessary evaluations.
• It prevents side effects from functions called in the boolean expressions when early termination occurs.

Binary Bits and Values

• A single binary bit can have two possible values: 0 or 1.
• Bytes, consisting of 8 bits, can represent 256 different values, ranging from 0 to 255 in decimal.

Binary Place Value Pattern

• In binary, the place value increases as powers of two from right to left: 2^0, 2^1, 2^2, etc.

Decimal Equivalent of Binary Numbers

• The binary number 100110 is equivalent to 38 in decimal.
• The binary value 101001 equals 41 in decimal.
• The binary number 101110 converts to 46 in decimal.
• The binary equivalent for decimal 174 is 10101110.
• The binary number 11110 corresponds to 30 in decimal.
• The decimal number 81 is represented as 1010001 in binary.
• The binary value for decimal 242 is 11110110.
• The binary value 10112, which appears to have an extra digit, would need clarification as it exceeds the binary format.

Bits for Decimal Representation

• A minimum of 8 bits are needed to represent the decimal number 209 in binary.

Data Storage with Bytes

• Chaining bytes facilitates efficient data storage and allows a larger range of values.

Information Representation

• The same bit pattern can represent various types of information, such as text and images, due to different encoding schemas.

Unicode Encoding

• Unicode supports a broad range of characters and symbols from various languages, promoting global communication.

Importance of Bit Size in Data Storage

• Bit size impacts the amount of data that can be stored and manipulated, affecting performance and space efficiency.

Example of Size Limitations

• The Legend of Zelda game (1986) exemplified size limitations by operating within strict data constraints, affecting graphics and gameplay.

Unique Unicode Features for Emojis

• Emojis are encoded in Unicode with unique code points, allowing consistent representation across multiple platforms.

Delve deeper into boolean expressions in computer science with this quiz. Learn about evaluating boolean expressions, short circuit evaluation, and how boolean expressions are similar to arithmetic expressions but with T/F values instead of numbers.