Not fully understanding the code in the example in "Learn to Program"

So I am not getting similar code to what Chris is when I do the examples he wants us to do, and many of the things he brings up after Chapter 6 seem to be lacking some explanation to create a full understanding so I can fully absorb the concept.

Everything in previous chapters, we would get similar looking stuff. It’s only now that we’ve gotten to branching and looping, and everything afterward that things completely fall apart for me.

Deaf Grandma

My code

puts ''
puts ''

gma = 'Grandma replies: HUH?! SPEAK UP, SONNY!'

year = ''

year_roll = rand(20)

gma_canhear = 'Grandma replies: NO, NOT SINCE ' + year + '!'

if year_roll == 0
	year = '1930'
	elsif year_roll == 1
		year = '1931'
		elsif year_roll == 2
			year = '1932'
			elsif year_roll == 3
				year = '1933'
				elsif year_roll == 4
					year = '1934'
					elsif year_roll == 5
						year = '1935'
						elsif year_roll == 6
							year = '1936'
							elsif year_roll == 7
								year =  '1937'
								elsif year_roll == 8
									year =  '1938'
									elsif year_roll == 9
										year =  '1939'
										elsif year_roll == 10
											year = '1940'
											elsif year_roll == 11
												year =  '1941'
												elsif year_roll == 12
													year = '1942'
													elsif year_roll == 13
														year = '1943'
														elsif year_roll == 14
															year = '1944'
															elsif year_roll == 15
																year = '1945'
																elsif year_roll == 16
																	year = '1946'
																	elsif year_roll == 17
																		year = '1947'
																		elsif year_roll == 18
																			year = '1948'
																			elsif year_roll == 19
																				year = '1949'
																				else year_roll == 20
																					year = '1950'																					
end

gma_canhear = 'Grandma replies: NO, NOT SINCE ' + year + '!' 
#Update gma_canhear variable with year value after the year_roll if branch.

wistg = 'a' 
# what I say to grandma = wistg | This is it's inital value before being updated. If I left it blank it 
# would cause an error. I don't know why.

while wistg != wistg.upcase
	puts 'You say to Grandma...'
	wistg = gets.chomp
	puts ''
		if wistg == wistg.upcase
			puts ''
			puts gma_canhear
			puts ''
			elsif wistg == 'BYE'
				break
				else 	puts gma
						puts ''
			end
end

puts ''
puts ''

Chris’ code

puts 'HEY THERE, SONNY! GIVE GRANDMA A KISS!'
while true
said = gets.chomp
if said == "BYE"
puts 'BYE SWEETIE!'
break
end
if said != said.upcase
puts 'HUH?! SPEAK UP, SONNY!'
else
random_year = 1930 + rand(21)
puts 'NO, NOT SINCE ' + random_year.to_s + '!'
end
end

or

puts 'HEY THERE, SONNY! GIVE GRANDMA A KISS!'
while true
said = gets.chomp
break if said == "BYE"
response = if said != said.upcase
'HUH?! SPEAK UP, SONNY!'
else
"NO, NOT SINCE #{rand(1930..1950)}!"
end
puts response
end
puts 'BYE SWEETIE!'

His code is vastly more compact. I just don’t understand how he was able to do that. I barely understand what he did.

I did what I could, with what I learned form the book up to that point and never in my wildest dreams would I have come up with anything like what he did.

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