CS Week 1 - Vector and Functions Review

Question 1

Radix sort

Answer 1

sort smaller pieces, than sort those pieces
- sorting last names, sort 26 stacks, put together sorted

Question 2

modular development

Answer 2

process of dividing a program into separate modules that can be developed and tested separately and then integrated into a single program

Question 3

incremental development

Answer 3

process in which a programmer writes, compiles, and tests a small amount of code, then writes compiles and tests a small amount more and so on

Question 4

function stub

Answer 4

function definition whose statements have not yet been written
- cout fixme
- helps capture the correct high-level behavior

Question 5

function

Answer 5

defined to compute a mathematical calculation involving several numerical parameters and a number result

Question 6

difference in using a function in main

Answer 6

void - a statement that calls it to cout or updates variables
any other type - a returned value use as an expression or cout it

Question 7

unit testing

Answer 7

process of individually testing a small part of a program, typically a function

Question 8

test bench

Answer 8

a separate program whose sole purpose is to check that a function returns the correct output values for a variety of inputs
- used to conduct unit testing

Question 9

test vector

Answer 9

each unique set of input values
- make sure you use border cases and inputs that thoroughly exercise the program

Question 10

what does assert() do, how to include and use

Answer 10

• tests your function in main
  # include <cassert>
  assert ( functionCall(arguments) == correct output );</cassert>
• if false, exits and tells you the line number and expression
• or cout that you are testing the input and the expected output and what you got by calling the function

Question 11

pass by value

Answer 11

arguments value is copied into a local variable for the parameter

Question 12

pass by reference

Answer 12

does not create a local copy of the argument, refers directly to the arguments
variable memory location
append & to type

Question 13

what is pass by reference for

Answer 13

changing the original variable
more than one return
big data types like strings and vectors

Question 14

reference variable

Answer 14

variable type that refers to another variable
type& name = other;

Question 15

scope

Answer 15

the name of a defined variable or function item is only visible to a part of a program
-starts after it is declared

Question 16

global variable and why it should be avoided

Answer 16

variable declared outside
any function
- reaches into functions
- better for constants
-a local defined with same name than global is ignored AND
-if a function changes it, its effects go beyond its return and parameters

Question 17

side effects

Answer 17

a function that updates a global variable has side effects that go beyond its parameters and return value

Question 18

function declaration

Answer 18

declared before main with everything but { } and statements
- ends with ;

Question 19

rand() and what to include

Answer 19

generates a random number
# include <cstdlib>
range from 0 to RAND_MAX</cstdlib>

Question 20

what to use to make the range of a random number

Answer 20

%

Question 21

how many possible values in rand() % N and what range

Answer 21

N possible values from 0 to N-1

Question 22

specific range of a random number

Answer 22

rand() % (large - small + 1) + small

Question 23

pseudo random

Answer 23

not actually but having the appearance of
- the ints generated by rand()

Question 24

how to get different sequence of random numbers and how each time

Answer 24

srand( seedYouWant);
- called once before rand()

srand(time());
#include <ctime></ctime>

Question 25

vector and what to include

Answer 25

ordered list of items of a given data type - an object
#inlcude <vector></vector>

Question 26

element

Answer 26

each item in a vector

Question 27

declare a vector with a size, with the same value, and all different values

Answer 27

vector<type> name (numElements);</type>

vector<type> name (numElements, value);</type>

vector<type> name = {value, value, ...};</type>

Question 28

how to find vector size

Answer 28

name..size();

Question 29

how to know if a vector is empty

Answer 29

name.empty()
- returns a bool
- 0 - false
- 1- true

Question 30

how to access an element in a vector and how to nth element

Answer 30

name.at(index);

index of nth element = n - 1

Question 31

difference between using v[index] and v.at(index)

Answer 31

v[index] faster but does not check if index is legal - not safe

v.at(index) check is an index is legal - slower but safer

Question 32

iterating through a vector

Answer 32

iterate .size() times

Question 33

how to hold aside memory for a vector and why

Answer 33

name.reserve(amount);
- does not change size, just holds memory
- when you add another index, it makes a copy of it all in new memory, give compiler an idea/guess of what memory to hold aside

Question 34

how to add a new element to a vector

Answer 34

v.push_back(elementToAdd);

Question 35

how to add an element to the beginning of a vector

Answer 35

v.push_front(elementToAdd);

Question 36

how to find/access the last element of a vector

Answer 36

v.back();
- returns last element

Question 37

how to get rid of the last element of a vector

Answer 37

v.pop_back();

Question 38

why can .at() be used on both side of =

Answer 38

because you can change its value and use its value

Question 39

vector copy operation

Answer 39

=
vecB = vecA
b is a copy of a

Question 40

vector equality operation

Answer 40

==
vecB == vecA
compares a and b

Question 41

how to reverse a vector

Answer 41

iterate .size() / 2 times
temp val = .at(i)
.at(i) = .at( .size() - 1- i);
.at( .size() - 1 - i ) = temp val

Question 42

auto

Answer 42

tells compiler to determine the variables type using the value we give it
auto v = 2;
compiler now knows its type can use auto in a loop with this variable
- this is the context you need to use auto elsewhere

Question 43

how to print the type of a variable

Answer 43

typeid( variableName).name()

Question 44

types of d, i, and PKc

Answer 44

d - double
i = int
PKc = string (point, const, char)
- a string is a const char*

Question 45

range based loop

Answer 45

• does not use an index
• copy first value of vector into a variable and run the loop until there are no more elements in the vector

for ( type variable : vector) {
cout &laquo_space;variable;
}

• use const and & so that variable is not changed and it just reads vector
• when variable is called, go find the address

for ( const auto(or type)& variable : vector) {
sum += x;
}
- add auto so that x holds the right type
—————————————–

• if variable is a reference, it will change the vector directly

for (type& n1 : vector) {
type n2;
cin&raquo_space; n2;
n1 = n2;
}

Question 46

what is cerr

Answer 46

not for normal output
errors

Question 47

what allows for this to work :
vector<type> name; and how would it look different if we did not include what makes it work</type>

Answer 47

using namespace std;

std : vector <type> name;</type>

Question 48

two first statements

Answer 48

include <iostream>
using namespace std;</iostream>

Question 49

how to test your input

Answer 49

if ( !cin) {
cerr &laquo_space;“bad” &laquo_space;endl;
}

Question 50

.good();
.eof();
.fail();
.bad();

Answer 50

good - returns true if no stream errors have occurred

eof - returns value of eofbit if end of line reached

fail - returns true if fail bit or bad bit is set/error for previous operation

bad - returns true of bad bit is set, indicating the stream is bad

Question 51

if ( conditional ) break;

if ( conditional) continue;

and where can you use these

Answer 51

• get out of loop
• skip this iteration
• in a loop before all other statements

Question 52

look over ch2, ch 4, ch 5, CH 6!!, ch 7, ch 8, ch 9 from 10A

Answer 52

:)