diff --git a/ciphers/merkle_hellman_cryptosystem.rb b/ciphers/merkle_hellman_cryptosystem.rb
index 9eb0e4a..42bfbfe 100755
--- a/ciphers/merkle_hellman_cryptosystem.rb
+++ b/ciphers/merkle_hellman_cryptosystem.rb
@@ -1,61 +1,60 @@
 require'openssl';
 
 class MerkleHellman
-	SMALLEST_KNAPSACK_ITEM = 2**32
-	STEP = 2**32
-	def initialize size
-		@size = size;
-		sum = SMALLEST_KNAPSACK_ITEM;
-		@easy_knapsack = size.times.map do|k|
-			x = sum + rand(STEP);
-			sum += x;
-			x;
-		end
-		
-		@n = sum + rand(STEP);
-		
-		loop do
-			@a = rand(0..@n);
-			break if @a.gcd(@n) == 1;
-		end
-		
-		@hard_knapsack = @easy_knapsack.map do|x|
-			(@a * x) % @n;
-		end
-		
-	end
-	
-	def encrypt msg
-		raise ArgumentError, "max length is #{@size/8} characters" if msg.length * 8 > @size;
-		c = 0;
-		msg.each_codepoint.reverse_each.with_index do|ch,i|
-			7.downto(0) do|j|
-				wj = ch.>>(j).& 1;
-				c += wj * @hard_knapsack[i*8+7-j]
-			end
-		end
-		c;
-	end
-	
-	def decrypt c
-		p = @a.to_bn.mod_inverse(@n).mod_mul(c,@n).to_i;
-		byte = 0;
-		msg = [ ];
-		@easy_knapsack.reverse_each.with_index do|x,i|
-			bit = 0;
-			if p >= x
-				p -= x;
-				bit = 1;
-			end
-			byte |= (bit << (i%8));
-			if i % 8 == 7
-				msg << byte.chr;
-				byte = 0;
-			end
-		end
-		msg.join;
-	end
-	attr_accessor :hard_knapsack;
+  SMALLEST_KNAPSACK_ITEM = 2**32
+  STEP = 2**32
+
+  def initialize size
+    @size = size;
+    sum = SMALLEST_KNAPSACK_ITEM;
+    @easy_knapsack = size.times.map do |k|
+      x = sum + rand(STEP);
+      sum += x;
+      x;
+    end
+    @n = sum + rand(STEP);
+
+    loop do
+      @a = rand(0..@n);
+      break if @a.gcd(@n) == 1;
+    end
+
+    @hard_knapsack = @easy_knapsack.map do |x|
+      (@a * x) % @n;
+    end
+  end
+
+  def encrypt msg
+    raise ArgumentError, "max length is #{@size/8} characters" if msg.length * 8 > @size;
+    c = 0;
+    msg.each_codepoint.reverse_each.with_index do |ch,i|
+      7.downto(0) do|j|
+        wj = ch.>>(j).& 1;
+        c += wj * @hard_knapsack[i*8+7-j]
+      end
+    end
+    c;
+  end
+
+  def decrypt c
+    p = @a.to_bn.mod_inverse(@n).mod_mul(c,@n).to_i;
+    byte = 0;
+    msg = [ ];
+    @easy_knapsack.reverse_each.with_index do |x,i|
+      bit = 0;
+      if p >= x
+        p -= x;
+        bit = 1;
+      end
+      byte |= (bit << (i%8));
+      if i % 8 == 7
+        msg << byte.chr;
+        byte = 0;
+      end
+    end
+    msg.join;
+  end
+  attr_accessor :hard_knapsack;
 end
 
 str = "Hello there, this is my plaintext";