restricted arrays

lib/using_restricted_array.rb

@@ -6,56 +6,118 @@
 
 # Calculates the length of the restricted array. All values are integers.
 # The restricted_array is terminated by 'nil' i.e. array[length] = nil
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(1)
 def length(array)
-  raise NotImplementedError
+  i = 0
+  until array[i].nil?
+    i += 1
+  end
+   i
+  # raise NotImplementedError
 end
 
 # Prints each integer values in the array
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(1)
 def print_array(array)
-  raise NotImplementedError
+  i = 0
+  until array[i].nil?
+    print array[i]
+    i += 1
+  end
+  # raise NotImplementedError #.new('array')
 end
 
 # For an unsorted array, searches for 'value_to_find'.
 # Returns true if found, false otherwise.
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(1)
 def search(array, length, value_to_find)
-  raise NotImplementedError
+  i = 0
+  until i == length
+    if array[i] == value_to_find
+      return true
+    end
+    i += 1
+  end
+  false# raise NotImplementedError
 end
 
 # Finds and returns the largest integer value the array
 # Assumes that the array is not sorted.
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(1)
 def find_largest(array, length)
-  raise NotImplementedError
+  max = array[0]
+  i = 1
+  until i == length
+    if max < array[i]
+      max = array[i]
+    end
+    i += 1
+  end
+  max
+  # raise NotImplementedError
 end
 
 # Finds and returns the smallest integer value in the array
 # Assumes that the array is not sorted.
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(1)
 def find_smallest(array, length)
-  raise NotImplementedError
+  min = array[0]
+  i = 1
+  while i < length
+    if min > array[i]
+      min = array[i]
+    end
+    i += 1
+  end
+  min
+  # raise NotImplementedError
 end
 
 # Reverses the values in the integer array in place
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(n)
+# Space complexity: O(1)
 def reverse(array, length)
-  raise NotImplementedError
+  i = 0
+  j = length - 1
+  while i < j
+    temp = array[i]
+    array[i] = array[j]
+    array[j] = temp
+    i += 1
+    j -= 1
+  end
+  array
+  # raise NotImplementedError
 end
 
 # For an array sorted in ascending order, searches for 'value_to_find'.
 # Returns true if found, false otherwise.
-# Time complexity: ?
-# Space complexity: ?
+# Time complexity: O(log n)
+# Space complexity: O(1)
 def binary_search(array, length, value_to_find)
-  raise NotImplementedError
+  mid = length / 2
+  i = 0
+  j = length - 1
+  while i < j
+    if array[mid] == value_to_find
+      return true
+    elsif array[mid] < value_to_find
+      i = mid
+      mid = i + j / 2
+    else
+      j = mid
+      mid = i + j / 2
+    end
+    i += 1
+    j -= 1
+  end
+  false
+  # raise NotImplementedError
 end
 
 # Helper method provided to sort the array in ascending order