Frances' Learn to Program commits

ch08-arrays.rb

@@ -0,0 +1,24 @@
+# Type as many words as we want (one word per line), continuing until we press Enter on an empty line
+# Repeat the words back to us in alphabetical order.
+# Test program thoroughly.
+
+words = []
+puts "Hello, why don't you type some lines? Enter one word per line. When you get fed up, press Enter on an empty line."
+
+userInputEmpty = false
+
+while userInputEmpty == false
+
+  word = gets.chomp
+
+  if word != ""
+    words.push word
+    puts "How about another word? Leave empty if you're done"
+
+  else
+    userInputEmpty = true
+  end
+end
+
+puts "And here is a lovely alphabetical list of your words!"
+puts words.sort

ch09-writing-your-own-methods/ask.rb

@@ -1,3 +1,39 @@
 def ask question
-  # your code here
-end
+  while true
+    puts question
+    reply = gets.chomp.downcase
+
+    if (reply == "yes" || reply == "no")
+      if reply == "yes"
+          return true
+      else
+          return false
+      end
+      break
+    else
+      puts 'Please answer "yes" or "no".'
+
+    end
+  end
+
+  answer
+end
+
+puts "Hello, and thank you for participating."
+puts
+
+ask "Do you like eating tacos?"
+ask "Do you like eating burritos?"
+wets_bed = ask "Do you wet the bed?"
+ask "Do you like eating chimichangas?"
+ask "Do you like eating sopapillas?"
+puts "Just a few more questions..."
+ask "Do you like drinking horchata?"
+ask "Do you like eating flautas?"
+
+puts
+puts "DEBRIEFING"
+puts "Thanks for taking part. Actually it wasn't about mexican food; it was about bed wetting."
+puts
+puts "And your answer to that question was..."
+puts wets_bed

ch09-writing-your-own-methods/old_school_roman_numerals.rb

@@ -1,3 +1,48 @@
+# Write a method that when passed an integer between 1 and 3000 (or so)
+# returns a string containing the proper old-school Roman numeral.
+
+# M = 1000
+# D = 500
+# C = 100
+# L = 50
+# X = 10
+# V = 5
+# I = 1
+
+# Hint: use the integer division and modulus methods
+
+# How many times does each of those roman numerals factor into numberRequested?
+
+# Example: 1759
+
+# 1 x 1000 = M
+# 1 x 500 = D
+# 2 x 100 = CC
+# 1 x 50 = L
+# 0 x 10 = no Xs
+# 1 x 5 = V
+# 4 x 1 = IIII
+
+# MDCCLVIIII
+
+# How many times does 1,000 go into it? Put that many Ms.
+# How many times does 500 go into the remainder? Put that many Ds.
+# How many times does 100 go into the remainder? Put that many Cs.
+# How many times does 50 go into the remainder? Put that many Ls.
+# How many times does 10 go into the remainder? Put that many Xs.
+# How many times does 5 go into the remainder? Put that many Vs.
+# How many times does 1 go into the remainder? Put that many Is.
+
 def old_roman_numeral num
-  # your code here
-end
+
+  numberMs = "M" * (num / 1000)
+  numberDs = "D" * ((num % 1000) / 500)
+  numberCs = "C" * ((num % 500) / 100)
+  numberLs = "L" * ((num % 100) / 50)
+  numberXs = "X" * ((num % 50) / 10)
+  numberVs = "V" * ((num % 10) / 5)
+  numberIs = "I" * ((num % 5) / 1)
+
+  return numberMs + numberDs + numberCs + numberLs + numberXs + numberVs + numberIs
+
+end

ch09-writing-your-own-methods/roman_numerals.rb

@@ -1,3 +1,54 @@
+# M = 1000
+# D = 500
+# C = 100
+# L = 50
+# X = 10
+# V = 5
+# I = 1
+
 def roman_numeral num
-  # your code here
-end
+
+  number1000s = (num / 1000)
+  number100s = (num % 1000) / 100
+  number10s = (num % 100) / 10
+  number1s = (num % 10) / 1
+
+  numberDs = (num % 1000) / 500
+  numberCs = (num % 500) / 100
+  numberLs = (num % 100) / 50
+  numberXs = (num % 50) / 10
+  numberVs = (num % 10) / 5
+  numberIs = (num % 5) / 1
+
+  result = "M" * number1000s
+
+  if number100s == 9
+    result = result + "CM"
+  elsif number100s == 4
+    result = result + "CD"
+  else
+    result = result + "D" * numberDs
+    result = result + "C" * numberCs
+  end
+
+  if number10s == 9
+    result = result + "XC"
+  elsif number10s == 4
+    result = result + "XL"
+  else
+    result = result + "L" * numberLs
+    result = result + "X" * numberXs
+  end
+
+  if number1s == 9
+    result = result + "IX"
+  elsif number1s == 4
+    result = result + "IV"
+  else
+    result = result + "V" * numberVs
+    result = result + "I" * numberIs
+  end
+
+  result
+
+end

ch10-nothing-new/dictionary_sort.rb

@@ -1,3 +1,42 @@
+# Okay how do we solve this in English?
+# For the purpose of comparison, we should just downcase everything
+# But if it were capitalised to begin with, it ought to remain so
+
 def dictionary_sort arr
-  # your code here
-end
+  recursive_sort arr, []
+end
+
+def recursive_sort unsorted_array, sorted_array
+
+  # If the unsorted array has no items in it, return the sorted array
+  if unsorted_array.length <= 0
+    return sorted_array
+  end
+
+  # Remove the last word from the unsorted array and put it into the variable smallest
+  smallest = unsorted_array.pop
+
+  # Create a new array called still_unsorted to hold all the other words
+  still_unsorted = []
+
+  # For each word in the unsorted array, see if it's smaller than the 'smallest' word that you took earlier
+  # If it is, put the smallest word back into the array, and replace 'smallest' with this new word
+  # If word is not smaller than the smallest, then push this word into the still unsorted array
+
+  unsorted_array.each do | word |
+
+    if word.downcase < smallest.downcase
+      still_unsorted.push smallest
+      smallest = word
+    else
+      still_unsorted.push word
+    end
+  end
+
+  # Put the smallest word into the sorted array
+  sorted_array.push smallest
+
+  # Now call the same recursive sort method to sort out the still_unsorted words
+  recursive_sort still_unsorted, sorted_array
+
+end

ch10-nothing-new/english_number.rb

@@ -1,3 +1,90 @@
 def english_number number
-  # your code here
+  if number < 0
+    return "Please enter a number that isn't negative."
+  end
+
+  if number == 0
+    return "zero"
+  end
+
+  num_string = ""
+
+  ones_place = ['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine']
+  tens_place = ['ten', 'twenty', 'thirty', 'forty', 'fifty', 'sixty', 'seventy', 'eighty', 'ninety']
+  teenagers = ['eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen']
+  zillions = [['hundred',2],
+              ['thousand', 3],
+              ['million', 6],
+              ['billion', 9],
+              ['trillion', 12],
+              ['quadrillion', 15],
+              ['quintillion', 18],
+              ['sextillion', 21],
+              ['septillion', 24],
+              ['octillion', 27],
+              ['nonillion', 30],
+              ['decillion', 33],
+              ['undecillion', 36],
+              ['duodecillion', 39],
+              ['tredecillion', 42],
+              ['quattuordecillion', 45],
+              ['quindecillion', 48],
+              ['sexdicillion', 51],
+              ['septendecillion', 54],
+              ['octodecillion', 57],
+              ['novembdecillion', 60],
+              ['vigintillion', 63],
+              ['googol', 100]]
+
+  left = number
+
+  while zillions.length > 0
+    zil_pair = zillions.pop
+    zil_name = zil_pair[0]
+    zil_base = 10 ** zil_pair[1]
+    write = left/zil_base
+    left = left - write*zil_base
+
+    if write > 0
+      prefix = english_number write
+      num_string = num_string + prefix + " " + zil_name
+      if left > 0
+        num_string = num_string + " "
+      end
+    end
+  end
+
+  write = left/10
+  left = left - write*10
+
+  if write > 0
+    if ((write == 1) and (left > 0))
+      num_string = num_string + teenagers[left-1]
+      left = 0
+    else
+      num_string = num_string + tens_place[write-1]
+    end
+
+    if left > 0
+      num_string = num_string + "-"
+    end
+  end
+
+  write = left
+  left = 0
+
+  if write > 0
+    num_string = num_string + ones_place[write-1]
+  end
+
+  num_string
+
 end
+
+# puts english_number 937234827364876238423423487686234
+# puts english_number 234987234982398798423
+# puts english_number 23432
+puts english_number 99
+puts english_number 234
+puts english_number 109238745102938560129834709285360238475982374561034
+# puts english_number 9898176572634765762999987987