Whiteboard problems

README.md

@@ -32,6 +32,16 @@ Then the call of `print(list)` should produce the following output:
 
 Your method should produce a single line of output (may wrap with long lists).
 
+def print_array(list)
+  str = ''
+  str += '[ '
+  for i in 0..list.length
+    str += arr[list] + ","
+  end
+  str += ']'
+  puts str
+end
+
 ## Problem #2
 Write a method named `stretch` that accepts an array of integers as a
 parameter and returns a **new** array twice as large as the original, where
@@ -49,6 +59,21 @@ is stretched into the pair 9, 9, the number 7 is stretched into 4, 3,
 the number 4 is stretched into 2, 2, the number 24 is stretched into 12,
 12 and the number 11 is stretched into 6, 5.)
 
+def stretch(list)
+  new_list = []
+  for i in 0..list.length
+    if list[i] % 2 == 0
+      2.times do
+        new_list << list[i]
+      end
+    else
+      new_list << list[i] + 1
+      new_list << list[i]
+    end
+  end
+  return new_list
+end
+
 ## Problem #3
 Write a method named `numUnique` that accepts a sorted array of integers
 as a parameter and **utilizes a hash to** calculate and return the number of
@@ -68,6 +93,18 @@ because this list contains 15 different values.
 
 If passed an empty list, your method should return **0**.
 
+def numUnique(list)
+  count = Hash.new
+
+  return 0 if list.length == 0
+
+  for i in 0..list.length
+    count[list[i]] = "present"
+  end
+
+  return count.length
+end
+
 ## Problem #4
 Write a method named `numUnique2` that functions the same as `numUnique`
 except that it **does NOT use a hash** to solve the problem. In this version,
@@ -76,3 +113,17 @@ outside of fixnum variables, if needed.
 
 Remember that you can assume that the values in the array appear in
 sorted (nondecreasing) order.
+`list = [1, 2, 11, 17, 19, 20, 23, 24, 25, 26, 31, 34, 37, 40, 41]`
+
+
+def numUnique2(list)
+  num = list[0]
+  count = 1
+  for i in 0..list.length
+    if list[i] != num
+      count += 1
+      num = list[i]
+    end
+  end
+  return count
+end