Control Flow

Question 1

What is control flow?

Answer 1

Control flow is that we can select different outcomes depending on the environment and the input.

Question 2

What is an if statement?

Answer 2

Ruby takes an if statement and decides if its true and runs code accordingly.

Question 3

What is an else statement?

Answer 3

The else statement is the continuation of the if statement. This code runs after the if statement is false.

Question 4

What is an elsif statement?

Answer 4

An elsif statement gives the if else statement more options.

Question 5

What is an unless statement?

Answer 5

An if statement checks if something is true, An unless statement checks if something is false and runs code accordingly.

Question 6

What is a comparator?

Answer 6

A comparator checks if two values are equal or not

we use == to check if they are equal and != if we want to check if two values are not equal.

Question 7

What are the comparator for less or equal than?

Answer 7

less than <

less than or equal to <=

greater than >

Greater than or equal to >=

Question 8

What are boolean operators?

Answer 8

Boolean operators are either true or false

• && (and)
• | | (or)
• ! (not)

Question 9

What is an and operator?

Answer 9

• && (and), The expression is true if both statements before and after && are true

true && true => true
true && false => false
false && true => false
false && false => false

Question 10

What is an Or-operator?

Answer 10

- | | (or) is an operator when at least one of the expressions are true
true || true # => true
true || false # => true
false || true # => true
false || false # => false

Question 11

What is an Not-operator?

Answer 11

A not operator (!) makes any statement after the expression false
!true= false

Question 12

What is gets.chomp?

Answer 12

Gets chomp is for getting user input from the terminal

Question 13

What is the .downcase method?

Answer 13

the .downcase method takes the user input and converts it do lower case letters.

Question 14

What is the .include? method

Answer 14

The include? method checks if the user input contains what we want

Question 15

What is the .gsub! method?

Answer 15

The .gsub method stands for global substitution and changes all the chosen inputs.

string_to_change.gsub!(/s/, “th”)

Question 16

What is string interpolation ?

Answer 16

String interpolation adds a value to a string.

print “Adios, #{my_string}!”

Question 17

What is a While loop?

Answer 17

The while loop runs code as long as the conditions are true.

counter = 1
while counter < 11
  puts counter
  counter = counter + 1
end

Question 18

What is an infinite loop?

Answer 18

An infinite loop is a loop that runs forever.

They need to be avoided at all cost.

Question 19

What is an untill loop?

Answer 19

An until loop runs as long as the conditions are not met.

i = 0
until i == 6
  i = i + 1
end
puts i

Question 20

What is an assignment operator?

Answer 20

An assignment operator is used to update a variable.

+=, -=, *=, and /=.

Question 21

What is an for loop?

Answer 21

The for loop runs a code between a range.

for current_iteration_number in 1..100 do
puts “Hello world, this is number #{current_iteration_number}”
end

Question 22

What is an inclusive range?

Answer 22

An inclusive range is a range that includes the last number in the range
1..3 (two dots)

for num in 1..20 (don’t forget the in)
puts num
end

Question 23

What is an exclusive range?

Answer 23

An exclusive range is a range where the last number is not included in the range.

1..3 (three dots)

for num in 1…20 (don’t forget the in)
puts num
end

Question 24

What is an iterator?

Answer 24

An iterator is just a Ruby method that repeatedly invokes a block of code.

Question 25

What is the next keyword?

Answer 25

The next keyword is used to skip a step.

Question 26

What is an array?

Answer 26

An array is a variable with multiple items in it
my_array = [1, 2, 3, 4]
An array is also indexed starting from 0.

Question 27

How do you get user input?

Answer 27

gets.chomp

Question 28

What is The .each Iterator ?

Answer 28

.each method, which can apply an expression to each element of an object, one at a time.

object.each do | item | 
  # Do something 
end

Question 29

What is the .times Iterator?

Answer 29

The .times method is like a super compact for loop: it can perform a task on each item in an object a specified number of times

10.times { print “Chunky bacon!” }

Question 30

What is the .split Method?

Answer 30

it takes in a string and returns an array. If we pass it a bit of text in parentheses, .split will divide the string wherever it sees that bit of text, called a delimiter. For example,

text.split(“,”)