ALC Final Exam
Static - correct answer ✔✔Variable type is checked at compile time
Dynamic - correct answer ✔✔Variable type is checked at runtime
Language evaluation criteria: Readability - correct answer ✔✔The ease with which programs can be read
and understood
Language evaluation criteria: Writability - correct answer ✔✔The ease with which a language can be
used to create programs
Language evaluation criteria: Reliability - correct answer ✔✔Conformance to specifications (i.e.,
performs to its specifications)
Language evaluation criteria: Cost - correct answer ✔✔The ultimate total cost
Phases of a compiler: Step 1 - correct answer ✔✔Lexical analysis: converts characters in the source
program into lexical units
Phases of a compiler: Step 2 - correct answer ✔✔Syntax analysis: transforms lexical units into parse trees
which represent the syntactic structure of program
Phases of a compiler: Step 3 - correct answer ✔✔Semantics analysis: further checks that are too difficult
for syntax (declare before use, type checking, parameter matching).
ALSO IN STEP 3: intermediate code generator
Phases of a compiler: Step 4 - correct answer ✔✔Code generation: machine code is generated
, Mark-and-sweep - correct answer ✔✔Garbage collection algorithm consisting of a mark phase and a
sweep phase.
Mark phase: when an object is created, its mark bit is set to false. In the mark phase, the mark bit of all
reachable objects is set to true.
Sweep phase: all objects whose marked value is false are cleared from memory.
Reference counting - correct answer ✔✔Garbage collection algorithm. Each object has a count of the
number of references to it. If an object has 0 references to it, it is identified as garbage and cleared from
memory.
Semaphore - correct answer ✔✔A data structure consisting of a counter and a queue for storing task
descriptors. Used to implement safeguards on the code that accesses shared data values and provides
synchronization between processes. Has a "wait" phase and a "release" phase.
Abstraction - correct answer ✔✔A view or representation of an entity that includes only the most
significant attributes
Abstract data type - correct answer ✔✔A user-defined data type in which the representation of objects
is hidden
https://www.youtube.com/watch?v=XkoeF-xXo2o
Binding - correct answer ✔✔An association between an entity and an attribute, such as between a
variable and its type or value, or between an operation and a symbol
Binding time - correct answer ✔✔The time at which a binding takes place
Static binding - correct answer ✔✔A binding is static if it first occurs before runtime and remains
unchanged throughout program execution
Dynamic binding - correct answer ✔✔A binding is dynamic if it first occurs during execution or can
change during execution of the program
Static - correct answer ✔✔Variable type is checked at compile time
Dynamic - correct answer ✔✔Variable type is checked at runtime
Language evaluation criteria: Readability - correct answer ✔✔The ease with which programs can be read
and understood
Language evaluation criteria: Writability - correct answer ✔✔The ease with which a language can be
used to create programs
Language evaluation criteria: Reliability - correct answer ✔✔Conformance to specifications (i.e.,
performs to its specifications)
Language evaluation criteria: Cost - correct answer ✔✔The ultimate total cost
Phases of a compiler: Step 1 - correct answer ✔✔Lexical analysis: converts characters in the source
program into lexical units
Phases of a compiler: Step 2 - correct answer ✔✔Syntax analysis: transforms lexical units into parse trees
which represent the syntactic structure of program
Phases of a compiler: Step 3 - correct answer ✔✔Semantics analysis: further checks that are too difficult
for syntax (declare before use, type checking, parameter matching).
ALSO IN STEP 3: intermediate code generator
Phases of a compiler: Step 4 - correct answer ✔✔Code generation: machine code is generated
, Mark-and-sweep - correct answer ✔✔Garbage collection algorithm consisting of a mark phase and a
sweep phase.
Mark phase: when an object is created, its mark bit is set to false. In the mark phase, the mark bit of all
reachable objects is set to true.
Sweep phase: all objects whose marked value is false are cleared from memory.
Reference counting - correct answer ✔✔Garbage collection algorithm. Each object has a count of the
number of references to it. If an object has 0 references to it, it is identified as garbage and cleared from
memory.
Semaphore - correct answer ✔✔A data structure consisting of a counter and a queue for storing task
descriptors. Used to implement safeguards on the code that accesses shared data values and provides
synchronization between processes. Has a "wait" phase and a "release" phase.
Abstraction - correct answer ✔✔A view or representation of an entity that includes only the most
significant attributes
Abstract data type - correct answer ✔✔A user-defined data type in which the representation of objects
is hidden
https://www.youtube.com/watch?v=XkoeF-xXo2o
Binding - correct answer ✔✔An association between an entity and an attribute, such as between a
variable and its type or value, or between an operation and a symbol
Binding time - correct answer ✔✔The time at which a binding takes place
Static binding - correct answer ✔✔A binding is static if it first occurs before runtime and remains
unchanged throughout program execution
Dynamic binding - correct answer ✔✔A binding is dynamic if it first occurs during execution or can
change during execution of the program
