Day 16 solution in Ruby (#160)

* Add @aaditkamat as a contributor

* Add Ruby code for Day 1: FizzBuzz problem

* Add Ruby code for Day 2: String reverse problem

* Update README.md for Day 2

* Modify Ruby code and README

* Add condition for nil and wrong type edge cases

* Add a seperate Ruby source code file for palindrome

* Modify code for reverse.rb

* Add seperate palindrome and reverse code sections in README

* Update gitignore

* Refactor palindrome.rb and rename heading in README

* Add solution for Day 3: Hamming Problem

* Add condition for strings of unequal lengths

* Update README

* Change project name and owner in.all-contributorsrc

* Remove merge conflict lines

* Add @shivank86 as a contributor

* Add C++ files for different patterns

* Add author and date comments at the top of C++ files

* Update README.md

* Add solution for Day 6 Problem in Python

* Update README

* Refactor code files

* Modify string representation of output in python files

* Add Ruby solutions for Day 6 problem

* Update README for Ruby code

* Add first version of solutions for Day 7 problem in C++, Java & Ruby

* Modify solutions

* Update Day 7 README

* Remove merge conflicts from CONTRIBUTORS.md

* Add back removed lines in CONTRIBUTORS.md

* Add code sections contributed by @imkaka to day 6 README

* Update README.md

* Add C++ solution

* Add Day 8 solution in C++

* Add Day 8 solution in Java

* Add Day 8 solution in Ruby

* Add Day 8 solution in Python

* Add credits at the top of the code

* Update README

* Update C++ implementation

* Update Python implementation

* Add solution for Day 10: String Permutation Problem in Python

Signed-off-by: Aadit Rahul Kamat <[email protected]>

* Update Day 10 README

Signed-off-by: Aadit Rahul Kamat <[email protected]>

* Change heading in README and remove empty directory in day 9

Signed-off-by: Aadit Rahul Kamat <[email protected]>

* Update README.md

* Add Ruby solutions for Day 13

* Update README

* Add credits to the code

* Add Python solution for Day 13

* Update Day 13 README

* Update fibonacci.py

* Modify Fibonacci python code section in day 13 README

* Add Ruby solution to Day 16 problem

Signed-off-by: Aadit Rahul Kamat <[email protected]>

* Update Day 16 README with Ruby implementation

Signed-off-by: Aadit Rahul Kamat <[email protected]>

* Change wording of print statement

Signed-off-by: Aadit Rahul Kamat <[email protected]>

Author: Aadit Kamat

day16/README.md

@@ -46,6 +46,44 @@ console.log ('\n/* ===== for 3 disks ===== */');
 towerOfHanoi (3, 'A', 'C', 'B');
 ```
 
+## Ruby Implementation
+
+### [Solution](./Ruby/hanoi.rb)
+
+```ruby
+=begin
+@author: aaditkamat
+@date: 12/01/2019
+=end
+
+def hanoi(start_rod, aux_rod, end_rod, num)
+  if num < 0
+    puts "The number of disks must be a non-negative integer"
+    return
+  end
+  if num == 0
+    return
+  end
+  if num == 1
+    puts "Move top most disk from rod #{start_rod} to rod #{end_rod}"
+    return
+  end
+  hanoi(start_rod, end_rod, aux_rod, num - 1)
+  hanoi(start_rod, aux_rod, end_rod, 1)
+  hanoi(aux_rod, start_rod, end_rod, num - 1)
+end
+
+def main
+  print "Enter number of disks: "
+  num = gets.chomp!.to_i
+  print "The sequence of instructions to move #{num} disks where disk 1 is the start rod"
+  puts "disk 2 is the auxiliary rod and disk 3 is the end rod are as follows: "
+  hanoi(1, 2, 3, num)
+end
+
+main
+```
+
 ## Python Implementation
 
 ### [Solution](./Python/tower_hanoi.py)
@@ -68,5 +106,4 @@ def towerhanoi(n, from_rod, to_rod, aux_rod):
 
 no_of_disks = int(input())
 towerhanoi(no_of_disks, 'A', 'C', 'B')
-
 ```

day16/Ruby/hanoi.rb

@@ -0,0 +1,31 @@
+=begin
+@author: aaditkamat
+@date: 12/01/2019
+=end
+
+def hanoi(start_rod, aux_rod, end_rod, num)
+  if num < 0
+    puts "The number of disks must be a non-negative integer"
+    return
+  end
+  if num == 0
+    return
+  end
+  if num == 1
+    puts "Move top most disk from rod #{start_rod} to rod #{end_rod}"
+    return
+  end
+  hanoi(start_rod, end_rod, aux_rod, num - 1)
+  hanoi(start_rod, aux_rod, end_rod, 1)
+  hanoi(aux_rod, start_rod, end_rod, num - 1)
+end
+
+def main
+  print "Enter number of disks: "
+  num = gets.chomp!.to_i
+  print "The sequence of instructions to move #{num} disks where disk 1 is the start rod"
+  puts "disk 2 is the auxiliary rod and disk 3 is the end rod are as follows: "
+  hanoi(1, 2, 3, num)
+end
+
+main