Merge pull request #463 from mwieder/reverse_ruby

implementation of game 73 (Reverse) in ruby

73_Reverse/ruby/reverse.rb

@@ -0,0 +1,111 @@
+ARRAYSIZE = 9
+$digitArray = Array.new(ARRAYSIZE)
+$winningArray = Array.new(ARRAYSIZE)
+
+# Method to print the rules
+def displayTheRules
+    puts "This is the game of 'Reverse'.  to win, all you have"
+    puts "to do is arrange a list of numbers (1 through " + ARRAYSIZE.to_s + ")"
+    puts "in numerical order from left to right.  to move, you"
+    puts "tell me how many numbers (counting from the left) to"
+    puts "reverse.  For example, if the current list is:"
+    puts "2 3 4 5 1 6 7 8 9"
+    puts "and you reverse 4, the result will be:"
+    puts "5 4 3 2 1 6 7 8 9"
+    puts "Now if you reverse 5, you win!"
+    puts "1 2 3 4 5 6 7 8 9"
+    puts "No doubt you will like this game, but"
+    puts "if you want to quit, reverse 0 (zero)."
+end
+
+# Method to print the list
+def printList
+    puts "\n" + $digitArray.join(" ") + "\n\n"
+end
+
+# Zero-based arrays contain digits 1-9
+# Make a random array and an ordered winning answer array A[0] to A[N]
+def makeRandomList
+    for kIndex in 0..ARRAYSIZE-1 do
+        $digitArray[kIndex] = kIndex+1
+        $winningArray[kIndex] = kIndex+1
+    end
+    # now randomize the digit array order
+    $digitArray.shuffle!
+end
+
+def checkForWin? (triesSoFar)
+    # Check for a win (all array elements in order)
+    if $digitArray == $winningArray then
+        puts "You won it in " + triesSoFar.to_s + " moves!!!\n\n"
+        puts "try again (yes or no)?"
+        tryAgain = gets.strip.upcase
+        if tryAgain == "YES" then
+            return true
+        end
+        puts "\nO.K. Hope you had fun!!"
+        exit
+    end
+    return false
+end
+
+def reverseIt (howManyToReverse, triesSoFar)
+    # REVERSE R NUMBERS AND PRINT NEW LIST
+
+    # extract and reverse the first howManyToReverse elements of the array
+    subArray = $digitArray.take(howManyToReverse)
+    subArray.reverse!
+    
+    # get the remaining elements of the original array
+    endArray = $digitArray.slice(howManyToReverse, ARRAYSIZE)
+    # append those elements to the reversed elements
+    $digitArray = subArray.concat(endArray)
+
+    # if we got all in order, randomize again
+    isWinner = checkForWin?(triesSoFar)
+    if isWinner == true then
+        makeRandomList
+    end
+    printList # always print the newly ordered list
+    return isWinner
+end
+
+def askHowManyToReverse
+    puts "How many shall I reverse?";
+    rNumber = gets.to_i
+    if rNumber > 0 then
+        if rNumber > ARRAYSIZE then
+            puts "Oops! Too many! I can reverse at most " + ARRAYSIZE.to_s
+        end
+    else
+        rNumber = 0 # zero or negative values end the game
+    end
+    return rNumber
+end
+
+puts "REVERSE"
+puts "Creative Computing  Morristown, New Jersey\n\n\n"
+puts "REVERSE -- A game of skill\n\n"
+
+puts "Do you want the rules?"
+wantRules = gets.strip.upcase
+if wantRules == "YES" then
+    displayTheRules
+end
+
+makeRandomList
+howManyTries = 0
+puts "\nHere we go ... the list is:"
+printList # display the initial list
+# start the game loop
+r = askHowManyToReverse
+while r != 0 do # zero will end the game
+    if r <= ARRAYSIZE then
+        howManyTries = howManyTries+1
+        if reverseIt(r, howManyTries) then
+            howManyTries = 0
+        end
+    end
+    r = askHowManyToReverse
+end
+