Chap 8 - programing python - print, if/elif/else, (nested) loops, len, string manipulation, arrays

Question 1

name 6 data types

Answer 1

-integer
-string
-boolean
-float
-character (char)
-date

Question 2

how do you use the print function

Answer 2

print(“ “)

Question 3

2 ways you can print messages on print function

Answer 3

-comma
-concatenation (adding)

Question 4

meaning of concatenation

Answer 4

join together

Question 5

how do you use comma when printing

Answer 5

use comma between words

Question 6

how do you use concatenation when printing

Answer 6

use ( + ) to add the strings

Question 7

what is the difference between using comma and concatenation

Answer 7

space in comma, no space in concatenation

Question 8

can you add strings

Answer 8

yes

Question 9

can you add strings and integers

Answer 9

no

Question 10

what data types are \t and \n

Answer 10

strings

Question 11

what must you put when using \t and \n

Answer 11

quotations

Question 12

what does \t do

Answer 12

a tab of space

Question 13

what does \n do

Answer 13

a new line

Question 14

what does = do

Answer 14

assignment of variable

Question 15

what does != mean

Answer 15

not equal

Question 16

3 rules for variables

Answer 16

-has to start with a char
-case sensitive
-no special char and spaces - willc hange program (except underscore)

Question 17

arithmetic operation for
-addition
-subtraction
-multiply
-divide
remainder
-power
-squared

Answer 17

• +
• -
• *
• / (float), // (integer)
• %
• **
• **(1/2)

Question 18

relational operation for:
-greater than
-greater than or equal
-smaller than
-smaller than or equal
-equal (Equality (eg, 2 obj, same 2 content))
-not equal (Equality (eg, 2 obj, same 2 content))

Answer 18

• >
• > =
• <
• <=
• ==
• !=

Question 19

logical operators

Answer 19

• and
• or
• not
  eg. if not hungry:

Question 20

bitwise operators for:
-bitwise AND
-bitwise OR
-bitwise NOT
-bitwise XOR
-bitwise left shift
-bitwise right shift

Answer 20

• &
• |
• ~
• «
• > >

Question 22

operation for identity true

Answer 22

is
-Identity (eg, 2 obj, 1 content) - refer back to same memory

Question 23

operation for identity false

Answer 23

is not
-Identity (eg, 2 obj, 1 content) - refer back to same memory

Question 24

operation for membership true

Answer 24

in
-Membership - check if value exists in a sequence

Question 25

operation for membership false

Answer 25

not in
-Membership - check if value exists in a sequence

Question 26

which takes place first: maths operations or assignment of variable

Answer 26

maths operations

Question 27

note: explain each thing when explaining assignment

Answer 27

eg. c = a=b
- c: variable
- +: addition of a and b
- =: assignment of variable

Question 28

equality vs identity vs memebership

Answer 28

equality - checks if obj has same contents (2 obj, same 2 content)
identity - check if obj are the same by refer back to same memory (2 obj, 1 content)
membership - check if value exists in a sequence

Question 29

what does = do

Answer 29

assignment of variables

Question 30

how do you find input for string

Answer 30

str(input(“ “))

Question 31

how do you find input for integer

Answer 31

int(input(“ “))

Question 32

how do you find input for float

Answer 32

float(input(“ “))

Question 33

can integer be stored in float, why

Answer 33

-yes
-integer requires less memory than float

Question 34

can float be stored in integer, why

Answer 34

-no
-float requires more memory than integer

Question 35

what is the drawback of integer and float stored as string

Answer 35

they’ll be used as a string - lose their properties kinda

Question 36

can integer and float be stored in string

Answer 36

yes

Question 37

can a string be an integer

Answer 37

no

Question 38

can a string be a float

Answer 38

-yes
-using float( )

Question 39

how do you use if conditional statement

Answer 39

if ( ):
, start here

Question 40

how do you use elif conditional statement

Answer 40

elif ( ):
, start here

Question 41

how do you use else conditional statement

Answer 41

else:
, start here

Question 42

how do you use nested ifs’

Answer 42

if ( ):
if ( ):

Question 43

how do you use and conditions in conditional statements

Answer 43

eg. if ( age> 10 and age< 20):

Question 44

how do you use conditional statement to get something in between value

Answer 44

eg. if (0 < username <10):

Question 45

how do you use or conditions in conditional statements

Answer 45

eg. if ( age> 10 or age< 20):

Question 46

nota: % - remainder, // - integer, / - float (for division)

Question 47

note: all chars are strings, not all strings are chars

Question 48

note: can add and & or to conditions

Question 49

Iteration

Answer 49

looping

Question 50

why are looped required

Answer 50

use same algorithm for diff. inputs

Question 51

types of loops

Answer 51

-for
-while

Question 52

basic structure of loops

Answer 52

-initializer- variable which controls if loop is done or not
-action
-stopping condition
-updating counter/ no. loops

Question 53

how to write for loop

Answer 53

-for i in range (__,__,_if you want__):
-for i in (variable/ list/ str)
-third one changes the steps between the loop
-don’t need to write iterating variable at start
(i changed to elements in variable/ list/ str)
(auto counter update)

Question 54

how to update counter

Answer 54

i = i+1
i +=1

Question 55

how to write while loop

Answer 55

i = 0
while (____):
i +=1
(manuel counter update)

Question 56

how does range function work

Answer 56

eg, (0, 5) - no.s - 0, 1, 2, 3, 4, - no 5
(0, 20, 2) - no.s 0-19, with 2 step btw (eg, 0, 2, 4…)
(variable/ list/ str) = no.s in that variable, list

Question 57

diff btw for & while loops

Answer 57

-for is repeated a known no. times
-while is repeated for unknown no. times

Question 58

what is i called in loops

Answer 58

iterating variable

Question 59

types of loop control statements

Answer 59

-break
-continue
-pass

Question 60

how to use break loop control

Answer 60

-write break within loop
-stop loop
-if used in nested loop, it stop the inner most loop

Question 61

how to use pass loop control

Answer 61

-write pass within loop
-acts as a placeholder and doesn’t print the i for that loop

Question 62

how to use continue loop control

Answer 62

-write continue within loop
-skips current iteration and jumps to next loop

Question 63

how to write loop/if/elif with a list as its range

Answer 63

n= [“A”, “B”]
-for i in n:
-while i in n:
-if variable[i] in n:
-elif variable[i] in n:
note: i changes to elements in list, list can be any data type

Question 64

index values in list

Answer 64

-all char has an index value
-first element = 0 - positive
-last element = -1 - negative

Question 65

index values of char in list

Answer 65

-first char is 0
-last char is -1

Question 66

note: space is considered a char so has an index value

Question 67

how to use len function

Answer 67

-finds no. elements in a list - list can be of any data types
n = [1,2,3]
length = len(n)
print(length)

Question 68

how to extract a certain char from a list

Answer 68

num = [1,2,3,4]
- print(num[ 0 ]) = 1
-print(num[ 0: ]) = 1, 2, 3, 4
-print(num[ 0:2]) = 1,2 (index after : not included)
-print(num[:2]) = 1,2 (index after : not included)
-print(num[-1]) = 4
-print(num[i:i+ n ]) = value with i index & n no.s after it

Question 69

diff btw in range of loops -

Answer 69

-for i in range (10, lengthData+10):
= i starts from 10th index - if range i beyond elements in list = index error
-for i in range (0, lengthData):
= i starts from 0th index

Question 70

how to print i in a single line in a loop

Answer 70

print( i, end=” “)

Question 71

how to use match case statements

Answer 71

match (variable):
case “something”:
action
case _:
action (only run when none of others match)
-use like if statements

Question 72

define array

Answer 72

-a sequence of elements of the same data type

Question 73

what the the index value of first element called

Answer 73

lower bound

Question 74

what the the index value of last element called

Answer 74

upper bound

Question 75

how do you create a blank array

Answer 75

-reserving memory in ram
-variable = [ None ] * (number of times)

Question 76

how to use blank array and string manipulation together

Answer 76

-variable [index number] = “ “
-for i in range ( , ):
variable [i] = ______
-while i < ___:
variable [i] = ______

Question 77

note: there are index values for each element in an array

Question 78

2 types of searching algorithms

Answer 78

-linear search
-binary search

Question 79

1 type of sorting algorithm

Answer 79

-bubble sort

Question 80

how does linear search work & its time

Answer 80

-compare target value with elements from left to right until they match (can be sorted or unsorted list)
-time: 0(n)

Question 81

advantages and disadvantages of linear search

Answer 81

advantages:
-fast for small to medium data sets
-works for sorted & unsorted sets
-good for data structures with no random access
disadvantages:
-slow for large data sets

Question 82

how does binary search work & its time

Answer 82

-check if target value if equal, bigger or smaller than the element in the middle
-eg, it’s smaller so all the elements smaller than the mid element and the mid element are left out in the next search
-continue until target value is found
-time: 0 (log n)

Question 83

advantages and disadvantages of binary search

Answer 83

advantages:
-quick
-good for large data sets
disadvantages:
-needs to be sorted

Question 84

how does bubble sort work & its time

Answer 84

-start with 1 chosen element
-compares adjacent elements to the chosen element and swaps them if needed until it is no longer needed
-time: 0 (n^2)

Question 85

advantages and disadvantages of bubble sort

Answer 85

disadvantages:
-bad for large data sets

Question 86

how to do nested for loops

Answer 86

-2 counters for inner and out loops
-outer loop only loops after inner loop is finished
eg. for j in range (0,3):
for i in range (0,2):
action

Question 87

what variable can you use for bubble sort

Answer 87

a temporary variable for the element swapping process

Question 88

how to make the bubble sort more efficient

Answer 88

-remove the already sorted elements
- eg. for j in range (0, len(variable) -1):
(outer loop)

Question 89

how to swap elements without a temporary variable

Answer 89

-ages [i], ages [i+1] = ages [i+1], ages [i]
1 2 2 1
Left to right:
1 goes to 2
2 goes to 1

Question 90

How does a post test loop work (not used in python)

Answer 90

-initialize loop counter
-execute action
-update counter
-check condition
-if condition met, stop
else repeat

Question 91

how does a pre test loop work

Answer 91

-initialize loop counter
-check condition
if condition met:
-execute action
-update counter

Question 92

what is a for loop also called

Answer 92

count control loop

Question 93

note: arrays cannot be implemented on python so just think of them like list with 1 data type

Question 94

what is a 2D list

Answer 94

a list made up of lists
eg.
fruits = [“apple”, “orange”, “banana”, “coconut”]
groceries = [“celery”, “carrots”, “potatoes”]
meats = [“chicken”, “fish”, “turkey”]
groceries = [fruits, groceries, meats]

Question 95

how to use a 2d list with variables to print each row or element

Answer 95

eg.
fruits = [“apple”, “orange”, “banana”, “coconut”]
vegetables = [“celery”, “carrots”, “potatoes”]
meats = [“chicken”, “fish”, “turkey”]
groceries = [fruits, vegetables, meats]
for a row:
-print(groceries [row index])
for a single element:
-print(groceries [row index] [column index])

-if index is too big, will give “list index out of range”
-each list is a row, each element is a column (like a matrix)

Question 96

how to use a 2d list without variables using a for loop to print each row or everything

Answer 96

groceries = [[“apple”, “orange”, “banana”, “coconut”],
[“celery”, “carrots”, “potatoes”],
[“chicken”, “fish”, “turkey”]]
for a row:
-for i in groceries:
print(i)
for everything in a matrix:
-for j in groceries:
for i in j:
print(i, end=” “)
print( )
for everything in a single line:
-for j in groceries:
for i in j:
print(i)

Question 97

what does end = “ “ do

Answer 97

rearranges the printed word in a single line

Question 98

what happens when you print a list

Answer 98

the list is printed with the parentheses

Question 99

note: for loop doesn’t check condition, only runs it

Question 100

pre- condition loop in pseudocode

Answer 100

while loop

Question 101

post- condition loop in pseudocode

Answer 101

REPEAT

Question 102

what is size of array

Answer 102

number of elements

Question 103

how to randomly choose an element

Answer 103

import random
random.choice( )