Add quick union logic and rspec test sample.

Needs more coverage.

Author: deepakhb2

union-find/quick-union.rb

@@ -0,0 +1,39 @@
+class QuickUnion
+  attr_reader :values, :size
+  def initialize(size)
+    @size = size
+    @values = Array.new(@size)
+    (0...@size).each do |i|
+      @values[i] = i
+    end
+  end
+
+  def root(p)
+    root = p
+    while(root != @values[root])
+      root = @values[root]
+    end
+    root
+  end
+
+  def connected(p, q)
+    return root(p) == root(q)
+  end
+
+  def union(p, q)
+    pr = root(p)
+    qr = root(q)
+    unless(pr == qr)
+      @values[pr] = qr
+    end    
+  end
+end
+
+qf = QuickUnion.new(10)
+p qf.values
+qf.union(4, 3)
+p qf.values
+qf.union(9, 8)
+p qf.values
+qf.union(4, 8)
+p qf.values

union-find/quick-union/quick_union.rb

@@ -0,0 +1,9 @@
+require_relative './quick_union'
+
+RSpec.describe QuickUnion do
+  it "Create array with values assigned to its index" do
+    qf = QuickUnion.new(10)
+    expect(qf.size).to eq(10)
+    expect(qf.values.size).to eq(10)
+  end
+end