Final

Question 1

Imperative Programming

Answer 1

Fundamental operation is the assignment statement

Control flow is dependent on the values of variables

Interpretation of code depends on program state

relies on side effects

Question 2

Functional Programming

Answer 2

Principal operation is function application (function calls)

functions bay be passed as arguments to other functions

Functions may be returned by functions

Question 3

Side effect

Answer 3

When a function relies on, or modifies, something outside its parameters to do something.

A function is pure if given the same inputs it:
- always returns the same output
- does not have any side effects

more difficult to reason about a program the relies on side effects

Question 4

Compiler

Answer 4

source to machine code to run later

Question 5

interpreter

Answer 5

source to run now

Question 6

transpiler

Answer 6

source to source

Question 7

syntax

Answer 7

How a program looks. Is specified / validated by a grammar

A program is syntactically valid if there is a parse tree
for the given grammar

Question 8

Semantics

Answer 8

what a program does

what a program means

Question 9

Sentence ( of grammar)

Answer 9

string of tokens from the grammar

Question 10

Sentential form

Answer 10

String of terminals & non terminals from the grammar

Question 11

derivation

Answer 11

sequence of sentential forms that starts with start symbols & ends with a sentence

a sentence is valid if there exists at least one derivation for it

Question 12

grammar

Answer 12

A set of instructions about how to write statements that are valid for that programming language.

Grammars consist of
* Non-terminals (or “syntactic categories”)
* Terminals
* Productions
* A start symbol/non-terminal

Question 13

Abstract Syntax Tree

Answer 13

A data structure that represents the text of a program

Question 14

Lexer

Answer 14

A program that takes source code & turns it into a stream of tokens

Question 15

Parser / Parsing

Answer 15

process of detecting whether a stream of tokens is a valid sentence in a grammar.

if fails : syntax error
if pass : return AST

Question 16

what is produced by a parser

Answer 16

AST

Abstract Syntax Tree

Question 17

briefly explain when type errors occur in different languages

Answer 17

statically typed: c, c++, java
- compile time

dynamically typed: python, ruby
- runtime

bonus:

SML cannot have runtime type errors

Question 18

explain the difference between java and python

Answer 18

java is statically typed
variables have types

python is dynamically typed
variables have values. The values have types

Question 19

HOF functions

Answer 19

Can take functions as parameters.
Can “build” functions that can be returned.
Functions can be “curried.” (built 1 param at a time)

Common HOFs

map, reduction (reduce, foldl, foldr), filter

Question 20

map

Answer 20

transform a list that looks one way into a list that looks a different way

uses a unary function

Question 21

filter

Answer 21

shrink a list

exclude certain values or include certain values

uses a unary function

Question 22

reduce

Answer 22

combine a list into 1 value

uses a binary function

Question 23

how would you use map

Answer 23

• map (fn x => x * 2) [1, 2, 3, 4];

val it = [2,4,6,8] : int list

Question 24

polymorphism

Answer 24

Allows objects of different classes to be treated as objects of a common superclass. This enables a single action to behave differently based on the object it is acting upon.

Question 25

how would you use filter in SML

Answer 25

Usage: filter (fn n => n mod 2 = 0); filter (fn n => n mod 2 = 0) [1,2,3,4,5];

Question 26

how would you use foldL / foldR in SML

Answer 26

(* Sum of all elements in a list *) val sum = foldl (fn (x, acc) => x + acc) 0 [1, 2, 3, 4] (* Result: 10 *)

Question 27

what does static mean in java

Answer 27

means that whatever is static belongs to the class not to any specific instance of the class you don't need to instantiate the class (make an Object based on your class) to use a static method.

Question 28

what is garbage collection

Answer 28

automatic memory management process that manages memory by identifying and reclaiming memory no longer in use prevents memory leaks is a part of JVM runtime (not compiler)

Question 29

explain marking and sweeping

Answer 29

marking is when during GC, all objects still being referenced are marked if a object survives long enough is is promoted to the next generation the GC then sweeps through the heap looking for memory to reclaim

Question 30

what is parent(eric, carson). what is eric what is carson

Answer 30

parent(eric, carson) is a fact eric and carson are atoms

Question 31

how to identify atom vs variable

Answer 31

lowercase is atom uppercase is variable

Question 32

what is ?- parent(eric, jenna). true.

Answer 32

a goal it asks is this true or can you make it true

Question 33

what is grandparent(G, C) :- parent(G, P), parent(P, C).

Answer 33

a rule

Question 34

what is a functor

Answer 34

a compoud data object that holds data together can be dynamic

Question 35

what is the number of arguments of a functor called?

Answer 35

the functors arity

Question 36

what does = do in prolog

Answer 36

it is a combination of assingment and equality depending on what the left and right side are free vs bound (variable vs atom) if both sides are bound check equal if one side is free, assign to match other side if both are free assignment is remembered and eventuyally verified

Question 37

what is ! in prolog

Answer 37

the cut operator. It stops the search after a successful unity

Question 38

where does the assembly code live for the JVM

Answer 38

in class files the class file is binary so not text but a series of bytes hence the name "bytecode"

Question 39

what is the left side called and what is the right side called aload 1

Answer 39

left side is opcode right side is operand

Question 40

what is the type for String

Answer 40

Ljava/lang/String

Question 41

what is the magic number

Answer 41

0xCAFEBABE

Question 42

is damlang statically typed or dynamically typed

Answer 42

dynamically it is implemented using a statically typed lang (java)

Question 43

what are the 2 types of parsers

Answer 43

top down (LL1) and bottom up (LALR1)

Question 44

what does LL1 mean

Answer 44

L Left-to-right scanning L While doing left-most derivation 1 only 1 symbol of lookahead is needed to chose next production

Question 45

what does LALR1 mean

Answer 45

LA LookAhead LR Input scanned L-to-R w/ right-most derivation 1 1 symbol lookahead

Question 46

is this LL1 or LALR1 5.* 4 + 3 T

Answer 46

LALR1

Question 47

does LL1 or LALR1 have the tree

Answer 47

LL1