Week 3 Flashcards
Data type for logical high and low data values (i.e., true or false)?
Bool
Value 0 evaluates as which Boolean value?
False
Value of anything other than zero evaluates as which Boolean value?
True
Order in which statements are executed in a program is referred to as?
The flow of control
The ordinary flow of control is?
Sequential
A statement used to alter the ordinarily sequential flow of control?
Control structure
An expression used by a control structure to determine the flow of control?
Branching condition
Control structure used to change flow of control between different alternatives?
Selection or branching
A statement of data values compored using logical operators is known as?
Logical expression, or assertion
Characteristics of the bool data type?
It holds only true or false, which are constants, and reserved words
Operators used to compare values in relational expressions are known as?
Relational operators
Relational operator == checks for?
Equality between to values
Relational operator != checks for?
Inequality between two values
Relational operator > checks for?
Greater than relationship
Relational operator < checks for?
Less than relationship
Relational operator => checks for?
Greater than or equal to
Relational operator =< checks for?
Less than or equal to
Chars are logically compared in what way?
Alphabetically, according to ASCII
Mixed type relational expressions are not always safe because?
Of implicit type coercion by the compiler
Bools compared with numerical data types evaluate as?
0 and 1
When comparing strings, one of them must be?
An identified string object as opposed to a literal C string
When comparing nonidentical strings, which string is considered less than the other?
The string where the first nonidentical character in both strings comes earlier in the ASCII table, or whichever is smaller if they match to the end of one of the strings
The fundamental control structure in C++ is?
The if statement
If statements evaluate a relational expression how?
If true else if false
What common algorithm uses if else statements?
Input validatiob
If a branching condition contains no relational operators, what is the behaviour?
Evaluates true if result not zero or null
If an if block contains another if block, how’s this referred?
Nested if
Nested ifs can be formatted…?
if
else if
else if
…
else
Logical operator && refers to?
AND operation
Logical operator || refers to?
OR operation
Logical operator ! refers to?
NOT operation, or inverse
If statements should only lead into else if clauses if?
The conditions are interdependent, or mutually exclusive
The final else is in an if else statement is called?
Dangling else
The dangling else is connected to which statement?
The most recent if statement that doesn’t have a connected else statement
What kind of evaluation methodology does C++ use for logical expressions?
Short-circuit evaluation
What is short circuit evaluation?
Evaluation in left to right order, which short circuits as soon as the compiler calculates the Boolean value for the entire expression
Which mathematical operation equates to the AND operator in Boolean algebra?
Multiplication
Which mathematical operation equates to the OR operation in Boolean algebra?
Addition
Which mathematical operation relates to the NOT operation in Boolean algebra?
Unary subtraction
Where do relational operators, the assignment operator and logical operators come in the order of precedence?
- Unary, *, %, /
- > < => =<
- == !=
- &&
- ||
- !
- =
Why is it not appropriate to check equality between floating point numbers?
Because tiny inaccuracies (due to the calculation and storage methods of real numbers) mean that rarely are two floating point numbers the same
How is it better to check for float equivalence?
std::fabs(a-b) > 0.00001
Where fabs (floating point absolute value) function returns difference
