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 integers

Answer 9

no

Question 10

what must you put when using \t and \n

Answer 10

quotations because they’re strings

Question 11

what does \t do

Answer 11

a tab of space

Question 12

what does \n do

Answer 12

a new line

Question 13

what does = do

Answer 13

assignment of variable

Question 14

what does != mean

Answer 14

not equal

Question 15

3 rules for variables

Answer 15

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

Question 16

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

Answer 16

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

Question 17

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 17

• >
• > =
• <
• <=
• ==
• !=

Question 18

logical operators

Answer 18

• and
• or
• not
  eg. if not hungry:

Question 19

operation for identity true

Answer 19

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

Question 20

operation for identity false

Answer 20

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

Question 21

operation for membership true

Answer 21

in
-Membership - check if value exists in a sequence

Question 22

operation for membership false

Answer 22

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

Question 23

which takes place first: maths operations or assignment of variable

Answer 23

maths operations

Question 24

note: explain each thing when explaining assignment

Answer 24

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

Question 25

equality vs identity vs memebership

Answer 25

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 26

what does = & == do

Answer 26

= - assignment of variables
== - comparison

Question 27

how do you find input for diff data types

Answer 27

str(input(“ “))
int(input(“ “))
float(input(“ “))

Question 28

1)can integer be stored in float, why
2)can float be stored in integer, why

Answer 28

1)yes, integer requires less memory than float
2)no, float requires more memory than integer

Question 29

what is the drawback of integer and float stored as string

Answer 29

they’ll be used as a string - lose their properties (can’t do mathematical operations on them)

Question 30

1)can integer and float be stored in string
2)can a string be an integer/ float

Answer 30

1)yes
2)no

Question 31

how do you use if conditional statement

Answer 31

if ( ):
, start here
-indentation

Question 32

how do you use elif conditional statement

Answer 32

elif ( ):
, start here
-indentation

Question 33

how do you use else conditional statement

Answer 33

else:
, start here
-indentation

Question 34

how do you use nested ifs

Answer 34

if ( ):
if ( ):
-indentation

Question 35

how do you use and & or conditions in conditional statements

Answer 35

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

Question 36

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

Answer 36

eg. if (0 < username <10):

Question 37

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

Question 38

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

Question 39

Iteration

Answer 39

looping

Question 40

why are looped required

Answer 40

use same algorithm for diff. inputs

Question 41

types of loops

Answer 41

-for
-while

Question 42

basic structure of loops

Answer 42

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

Question 43

how to write for loop

Answer 43

-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 44

how to update counter

Answer 44

i = i+1
i +=1

Question 45

how to write while loop

Answer 45

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

Question 46

how does range function work

Answer 46

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 47

diff btw for & while loops

Answer 47

-for - knows how many times to run = count controlled
-while - checks iterating value before running = precondition

Question 48

types of loop control statements

Answer 48

-break
-continue
-pass

Question 49

how to use break loop control

Answer 49

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

Question 50

how to use pass loop control

Answer 50

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

Question 51

how to use continue loop control

Answer 51

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

Question 52

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

Answer 52

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

Question 53

index values in list

Answer 53

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

Question 54

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

Question 55

how to use len function

Answer 55

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

Question 56

how to extract a certain char from a list

Answer 56

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 57

diff btw in range of loops -

Answer 57

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

Question 58

how to print i in a single line in a loop

Answer 58

print( i, end=” “)

Question 59

how to use match case statements

Answer 59

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

Question 60

define array

Answer 60

-a sequence of elements of the same data type

Question 61

what the the index value of first element called

Answer 61

lower bound

Question 62

what the the index value of last element called

Answer 62

upper bound

Question 63

how do you create a blank 1D array

Answer 63

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

Question 64

how to use blank array and string manipulation together

Answer 64

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

Question 65

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

Question 66

2 types of searching algorithms

Answer 66

-linear search
-binary search

Question 67

1 type of sorting algorithm

Answer 67

-bubble sort

Question 68

how does linear search work & its time

Answer 68

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

Question 69

advantages and disadvantages of linear search

Answer 69

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 70

how does binary search work & its time

Answer 70

-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 71

advantages and disadvantages of binary search

Answer 71

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

Question 72

how does bubble sort work & its time

Answer 72

-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 73

advantages and disadvantages of bubble sort

Answer 73

disadvantages:
-bad for large data sets

Question 74

how to do nested for loops

Answer 74

-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 75

what variable can you use for bubble sort

Answer 75

a temporary variable for the element swapping process

Question 76

how to make the bubble sort more efficient

Answer 76

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

Question 77

how to swap elements without a temporary variable

Answer 77

-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 78

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

Answer 78

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

Question 79

how does a pre test loop work

Answer 79

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

Question 80

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

Question 81

what is a 2D list

Answer 81

a list made up of lists
eg.
meats = [“chicken”, “fish”, “turkey”]
groceries = [fruits, groceries, meats]

Question 82

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

Answer 82

for a row:
-print(groceries [row])
for a single element:
-print(groceries [row] [column])

-each list is a row, each element is in a column (like a table)

Question 83

define traversing

Answer 83

accessing individual elements in 2D array

Question 84

how to traverse

Answer 84

groceries = [[“apple”, “orange”, “banana”, “coconut”],
[“celery”, “carrots”, “potatoes”],
[“chicken”, “fish”, “turkey”]]
-for j in groceries:
for i in j:
print(i)
-for row in range ( , ):
for column in range ( , ):
print(groceries [row] [column])
-finish inner loop before changing outer loop
row, column:
0, 0
0, 1
1, 0
1, 1

Question 85

what does end = “ “ do

Answer 85

rearranges the printed word in a single line

Question 86

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

Question 87

pre- condition loop in pseudocode

Answer 87

while loop

Question 88

post- condition loop in pseudocode

Answer 88

REPEAT

Question 89

what is size of array

Answer 89

number of elements

Question 90

how to randomly choose an element

Answer 90

import random
random.choice( )
random.randint( ) / random.randstr ( ) / random.randfloat ( )

Question 91

how to add time

Answer 91

import time
time.sleep( )
-in seconds

Question 92

what happens if index is too big

Answer 92

index out of range error

Question 93

how to create empty 2D array

Answer 93

array = [ [ 0 for column in range ( , )] for row in range ( , )]
-can replace 0 with None or “ string” to fill in the blank array

Question 94

order of row & column in 2D array when:
1)creating array
2)printing array
3)traversing
mark row = 1, column = 2

Answer 94

1) column, row 2, 1
2) row, column 1, 2
3) row, column 1, 2

Question 95

what can you do with traversing

Answer 95

-print each elements
-add data into 2D array eg. input or adding

Question 95

difference between for i in range ( , ) & for i in array when comparing & printing Found/ Not found

Answer 95

for i in range ( , ):
-print Found/ Not found as many times as range
for i in array:
-print Found/ Not found 1 time

Question 96

note:
before making 2D array - make a table look alike of it
mark row = 1, column = 2

Question 97

difference btw 1D & 2D array in terms of memory

Answer 97

1D - data is stored randomly in memory cell = more comparisons to find them
2D - data is stored consecutively in memory cell = less comparisons to find them

Question 98

help for arrays:
https://docs.google.com/document/d/1b5Tt-2W5yVyTZYWSwUQk3DXtFnfM_McnkaAZX1FV1QQ/edit?tab=t.0#heading=h.isd4beaopm41