From 99dfd151a3601c935b5649c454bd7e8d734c3f64 Mon Sep 17 00:00:00 2001 From: India Kato Date: Mon, 14 Dec 2020 14:04:30 -0800 Subject: [PATCH 1/3] add_first and get_first tests passing --- .idea/.gitignore | 6 ++++ .idea/inspectionProfiles/Project_Default.xml | 6 ++++ .idea/linked-lists.iml | 27 +++++++++++++++ .idea/misc.xml | 4 +++ .idea/modules.xml | 8 +++++ .idea/vcs.xml | 6 ++++ Gemfile.lock | 36 ++++++++++++++++++++ lib/linked_list.rb | 4 +-- test/linked_list_test.rb | 2 +- 9 files changed, 96 insertions(+), 3 deletions(-) create mode 100644 .idea/.gitignore create mode 100644 .idea/inspectionProfiles/Project_Default.xml create mode 100644 .idea/linked-lists.iml create mode 100644 .idea/misc.xml create mode 100644 .idea/modules.xml create mode 100644 .idea/vcs.xml create mode 100644 Gemfile.lock diff --git a/.idea/.gitignore b/.idea/.gitignore new file mode 100644 index 0000000..8bf4d45 --- /dev/null +++ b/.idea/.gitignore @@ -0,0 +1,6 @@ +# Default ignored files +/shelf/ +/workspace.xml +# Datasource local storage ignored files +/dataSources/ +/dataSources.local.xml diff --git a/.idea/inspectionProfiles/Project_Default.xml b/.idea/inspectionProfiles/Project_Default.xml new file mode 100644 index 0000000..b0db9b0 --- /dev/null +++ b/.idea/inspectionProfiles/Project_Default.xml @@ -0,0 +1,6 @@ + + + + \ No newline at end of file diff --git a/.idea/linked-lists.iml b/.idea/linked-lists.iml new file mode 100644 index 0000000..a1a27da --- /dev/null +++ b/.idea/linked-lists.iml @@ -0,0 +1,27 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + \ No newline at end of file diff --git a/.idea/misc.xml b/.idea/misc.xml new file mode 100644 index 0000000..510e7fc --- /dev/null +++ b/.idea/misc.xml @@ -0,0 +1,4 @@ + + + + \ No newline at end of file diff --git a/.idea/modules.xml b/.idea/modules.xml new file mode 100644 index 0000000..fae548e --- /dev/null +++ b/.idea/modules.xml @@ -0,0 +1,8 @@ + + + + + + + + \ No newline at end of file diff --git a/.idea/vcs.xml b/.idea/vcs.xml new file mode 100644 index 0000000..94a25f7 --- /dev/null +++ b/.idea/vcs.xml @@ -0,0 +1,6 @@ + + + + + + \ No newline at end of file diff --git a/Gemfile.lock b/Gemfile.lock new file mode 100644 index 0000000..630ea95 --- /dev/null +++ b/Gemfile.lock @@ -0,0 +1,36 @@ +GEM + remote: https://rubygems.org/ + specs: + ansi (1.5.0) + builder (3.2.4) + coderay (1.1.3) + method_source (1.0.0) + minitest (5.14.2) + minitest-reporters (1.4.2) + ansi + builder + minitest (>= 5.0) + ruby-progressbar + minitest-skip (0.0.3) + minitest (~> 5.0) + minitest-spec (0.0.2.1) + minitest (>= 3.0) + pry (0.13.1) + coderay (~> 1.1) + method_source (~> 1.0) + rake (13.0.1) + ruby-progressbar (1.10.1) + +PLATFORMS + ruby + +DEPENDENCIES + minitest + minitest-reporters + minitest-skip + minitest-spec + pry + rake + +BUNDLED WITH + 2.1.4 diff --git a/lib/linked_list.rb b/lib/linked_list.rb index 9e97557..19641a3 100644 --- a/lib/linked_list.rb +++ b/lib/linked_list.rb @@ -10,13 +10,13 @@ def initialize # Time complexity - ? # Space complexity - ? def add_first(data) - + @head = Node.new(data, @head) end # Time complexity - ? # Space complexity - ? def get_first - + return @head ? @head.data : nil end # Time complexity - ? diff --git a/test/linked_list_test.rb b/test/linked_list_test.rb index bdbbd06..61e74e8 100644 --- a/test/linked_list_test.rb +++ b/test/linked_list_test.rb @@ -21,7 +21,7 @@ end end - xdescribe 'add_first & get_first' do + describe 'add_first & get_first' do it 'can add values to an empty list' do # Act @list.add_first(3) From 3873fbc47f2bca528757c729c1826ac16430f4be Mon Sep 17 00:00:00 2001 From: India Kato Date: Mon, 14 Dec 2020 14:14:37 -0800 Subject: [PATCH 2/3] length with tests passing --- lib/linked_list.rb | 17 ++++++++++++----- test/linked_list_test.rb | 2 +- 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/lib/linked_list.rb b/lib/linked_list.rb index 19641a3..7c2e773 100644 --- a/lib/linked_list.rb +++ b/lib/linked_list.rb @@ -7,14 +7,14 @@ def initialize @head = nil end - # Time complexity - ? - # Space complexity - ? + # Time complexity - O(1) + # Space complexity - O(1) def add_first(data) @head = Node.new(data, @head) end - # Time complexity - ? - # Space complexity - ? + # Time complexity - O(1) + # Space complexity - O(1) def get_first return @head ? @head.data : nil end @@ -22,7 +22,14 @@ def get_first # Time complexity - ? # Space complexity - ? def length - return 0 + count = 0 + current = @head + + while current != nil + count += 1 + current = current.next + end + return count end # Time complexity - ? diff --git a/test/linked_list_test.rb b/test/linked_list_test.rb index 61e74e8..f109c2a 100644 --- a/test/linked_list_test.rb +++ b/test/linked_list_test.rb @@ -51,7 +51,7 @@ end end - xdescribe "length" do + describe "length" do it "will return 0 for an empty list" do expect(@list.length).must_equal 0 end From f781e61075cef048a7ed99666aedffddc1b1c38d Mon Sep 17 00:00:00 2001 From: India Kato Date: Mon, 14 Dec 2020 15:07:48 -0800 Subject: [PATCH 3/3] add_last, get_last, get_at_index with tests passing --- lib/linked_list.rb | 44 ++++++++++++++++++++++++++++++++-------- test/linked_list_test.rb | 4 ++-- 2 files changed, 37 insertions(+), 11 deletions(-) diff --git a/lib/linked_list.rb b/lib/linked_list.rb index 7c2e773..aacfddc 100644 --- a/lib/linked_list.rb +++ b/lib/linked_list.rb @@ -19,8 +19,8 @@ def get_first return @head ? @head.data : nil end - # Time complexity - ? - # Space complexity - ? + # Time complexity - O(n) + # Space complexity - O(n) def length count = 0 current = @head @@ -32,21 +32,47 @@ def length return count end - # Time complexity - ? - # Space complexity - ? + # Time complexity - O(n) + # Space complexity - O(n) def add_last(data) + new_node = Node.new(data) + if @head.nil? + @head = new_node + else + current = @head + until current.next.nil? + current = current.next + end + current.next = new_node + end end - # Time complexity - ? - # Space complexity - ? + # Time complexity - O(n) + # Space complexity - O(1) def get_last + return nil if @head.nil? + current = @head + + until current.next.nil? + current = current.next + end + return current.data end - # Time complexity - ? - # Space complexity - ? + # Time complexity - O(n) + # Space complexity - O(1) def get_at_index(index) - + return nil if @head.nil? + current = @head + index.times do + if current.next.nil? + return nil + else + current = current.next + end + end + return current.data end end diff --git a/test/linked_list_test.rb b/test/linked_list_test.rb index f109c2a..8e558e7 100644 --- a/test/linked_list_test.rb +++ b/test/linked_list_test.rb @@ -66,7 +66,7 @@ end end - xdescribe "addLast & getLast" do + describe "addLast & getLast" do it "will add to the front if the list is empty" do @list.add_last(1) expect(@list.get_first).must_equal 1 @@ -93,7 +93,7 @@ end end - xdescribe 'get_at_index' do + describe 'get_at_index' do it 'returns nil if the index is outside the bounds of the list' do expect(@list.get_at_index(3)).must_be_nil end