From 89a2446ceff584f9f079a7f6c74e20a38a3c7109 Mon Sep 17 00:00:00 2001
From: Andrey Ivanov <tiburon-777@users.noreply.github.com>
Date: Mon, 22 Jun 2020 17:06:12 +0300
Subject: [PATCH 1/4] =?UTF-8?q?=D0=9F=D1=80=D0=BE=D0=BC=D0=B5=D0=B6=D1=83?=
=?UTF-8?q?=D1=82=D0=BE=D1=87=D0=BD=D1=8B=D0=B9=20=D0=BA=D0=BE=D0=BC=D0=BC?=
=?UTF-8?q?=D0=B8=D1=82?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
---
hw04_lru_cache/cache.go | 50 +++++++++++++++---
hw04_lru_cache/cache_test.go | 26 ++++++++-
hw04_lru_cache/go.mod | 2 +-
hw04_lru_cache/list.go | 100 ++++++++++++++++++++++++++++++++---
hw04_lru_cache/list_test.go | 83 ++++++++++++++++++++++-------
5 files changed, 224 insertions(+), 37 deletions(-)
diff --git a/hw04_lru_cache/cache.go b/hw04_lru_cache/cache.go
index 738399e..dd93cfd 100644
--- a/hw04_lru_cache/cache.go
+++ b/hw04_lru_cache/cache.go
@@ -3,20 +3,54 @@ package hw04_lru_cache //nolint:golint,stylecheck
type Key string
type Cache interface {
- // Place your code here
+ Set(key Key, value interface{}) bool // Добавить значение в кэш по ключу
+ Get(key Key) (interface{}, bool) // Получить значение из кэша по ключу
+ Clear() // Очистить кэш
}
type lruCache struct {
- // Place your code here:
- // - capacity
- // - queue
- // - items
+ capacity int
+ queue *List
+ items map[Key]*ListItem
}
-type cacheItem struct {
- // Place your code here
+type Item struct {
+ Key Key
+ Value interface{}
}
func NewCache(capacity int) Cache {
- return &lruCache{}
+ return &lruCache{
+ capacity: capacity,
+ queue: NewList(),
+ items: map[Key]*ListItem{},
+ }
+}
+
+func (l *lruCache) Set(key Key, value interface{}) bool {
+ if _, exists := l.Get(key); exists {
+ l.items[key].Value = value
+ return exists
+ }
+ if l.queue.Len() >= l.capacity {
+ // TODO: нужно как-то удалить элемент из мапа
+ //delete(l.items,l.queue.Back().(*Item).Key)
+ l.queue.Remove(l.queue.Back())
+ }
+ l.items[key] = l.queue.PushFront(value)
+ return false
+}
+
+func (l *lruCache) Get(key Key) (interface{}, bool) {
+ if l.items[key] == nil {
+ return nil, false
+ }
+ l.queue.MoveToFront(l.items[key])
+ return l.items[key].Value, true
+}
+
+func (l *lruCache) Clear() {
+ l.items = nil
+ l.queue.len = 0
+ l.queue.Info = ListItem{}
}
diff --git a/hw04_lru_cache/cache_test.go b/hw04_lru_cache/cache_test.go
index e99447d..fd3ea5c 100644
--- a/hw04_lru_cache/cache_test.go
+++ b/hw04_lru_cache/cache_test.go
@@ -50,7 +50,31 @@ func TestCache(t *testing.T) {
})
t.Run("purge logic", func(t *testing.T) {
- // Write me
+ c := NewCache(3)
+
+ wasInCache := c.Set("aaa", 100)
+ require.False(t, wasInCache)
+
+ wasInCache = c.Set("bbb", 200)
+ require.False(t, wasInCache)
+
+ wasInCache = c.Set("ccc", 300)
+ require.False(t, wasInCache)
+
+ _, ok := c.Get("bbb")
+ require.True(t, ok)
+
+ _, ok = c.Get("aaa")
+ require.True(t, ok)
+
+ wasInCache = c.Set("ddd", 400)
+ require.False(t, wasInCache)
+
+ _, ok = c.Get("ddd")
+ require.True(t, ok)
+
+ _, ok = c.Get("ccc")
+ require.False(t, ok)
})
}
diff --git a/hw04_lru_cache/go.mod b/hw04_lru_cache/go.mod
index b4abc63..ba531d5 100644
--- a/hw04_lru_cache/go.mod
+++ b/hw04_lru_cache/go.mod
@@ -1,4 +1,4 @@
-module github.com/fixme_my_friend/hw04_lru_cache
+module github.com/tiburon-777/HW_OTUS/hw04_lru_cache
go 1.14
diff --git a/hw04_lru_cache/list.go b/hw04_lru_cache/list.go
index eab309f..8e7db93 100644
--- a/hw04_lru_cache/list.go
+++ b/hw04_lru_cache/list.go
@@ -1,17 +1,101 @@
package hw04_lru_cache //nolint:golint,stylecheck
-type List interface {
- // Place your code here
+type ListInterface interface {
+ Len() int // длина списка
+ Front() *ListItem // первый Item
+ Back() *ListItem // последний Item
+ PushFront(v interface{}) *ListItem // добавить значение в начало
+ PushBack(v interface{}) *ListItem // добавить значение в конец
+ Remove(i *ListItem) // удалить элемент
+ MoveToFront(i *ListItem) // переместить элемент в начало
}
-type listItem struct {
- // Place your code here
+type ListItem struct {
+ Value interface{} // значение
+ Next *ListItem // следующий элемент
+ Prev *ListItem // предыдущий элемент
}
-type list struct {
- // Place your code here
+type List struct {
+ Info ListItem
+ len int
}
-func NewList() List {
- return &list{}
+func NewList() *List {
+ return &List{len: 0}
+}
+
+func (l *List) Len() int {
+ return l.len
+}
+
+func (l *List) Front() *ListItem {
+ return l.Info.Next
+}
+
+func (l *List) Back() *ListItem {
+ return l.Info.Prev
+}
+
+func (l *List) PushFront(v interface{}) *ListItem {
+ e := &ListItem{Value: v}
+ if l.len != 0 {
+ e.Prev = l.Info.Next
+ l.Info.Next.Next = e
+ } else {
+ l.Info.Prev = e
+ }
+ l.Info.Next = e
+ l.len++
+ return e
+}
+
+func (l *List) PushBack(v interface{}) *ListItem {
+ e := &ListItem{Value: v}
+ if l.len != 0 {
+ e.Next = l.Info.Prev
+ l.Info.Prev.Prev = e
+ } else {
+ l.Info.Next = e
+ }
+ l.Info.Prev = e
+ l.len++
+ return e
+}
+
+func (l *List) Remove(i *ListItem) {
+ if i.Prev == nil {
+ i.Prev = &ListItem{}
+ l.Info.Prev = i.Next
+ }
+ if i.Next == nil {
+ i.Next = &ListItem{}
+ l.Info.Next = i.Prev
+ }
+ i.Prev.Next = i.Next
+ i.Next.Prev = i.Prev
+ if l.Len() > 1 {
+ l.Info.Next.Next = nil
+ l.Info.Prev.Prev = nil
+ } else {
+ l.Info = ListItem{}
+ }
+ l.len--
+}
+
+func (l *List) MoveToFront(i *ListItem) {
+ if l.Info.Next == i {
+ return
+ }
+ if i.Prev != nil {
+ i.Prev.Next = i.Next
+ i.Next.Prev = i.Prev
+ } else {
+ i.Next.Prev = i.Prev
+ l.Info.Prev = i.Next
+ }
+ i.Prev = l.Front()
+ l.Front().Next = i
+ i.Next = nil
+ l.Info.Next = i
}
diff --git a/hw04_lru_cache/list_test.go b/hw04_lru_cache/list_test.go
index 02109fd..a219aab 100644
--- a/hw04_lru_cache/list_test.go
+++ b/hw04_lru_cache/list_test.go
@@ -18,14 +18,50 @@ func TestList(t *testing.T) {
t.Run("complex", func(t *testing.T) {
l := NewList()
- l.PushFront(10) // [10]
- l.PushBack(20) // [10, 20]
- l.PushBack(30) // [10, 20, 30]
- require.Equal(t, l.Len(), 3)
+ l.PushFront(10)
+ require.Equal(t, []int{10}, transpond(l))
+ require.Equal(t, 1, l.Len())
+
+ l.Remove(l.Front())
+ require.Equal(t, []int{}, transpond(l))
+ require.Equal(t, 0, l.Len())
+
+ l.PushFront(10)
+ require.Equal(t, []int{10}, transpond(l))
+ require.Equal(t, 1, l.Len())
+
+ l.PushBack(20)
+ require.Equal(t, []int{20, 10}, transpond(l))
+ require.Equal(t, 2, l.Len())
+
+ l.PushBack(30)
+ require.Equal(t, []int{30, 20, 10}, transpond(l))
+ require.Equal(t, 3, l.Len())
middle := l.Back().Next // 20
- l.Remove(middle) // [10, 30]
- require.Equal(t, l.Len(), 2)
+ l.Remove(middle)
+ require.Equal(t, []int{30, 10}, transpond(l))
+ require.Equal(t, 2, l.Len())
+
+ l.PushFront(20)
+ require.Equal(t, []int{30, 10, 20}, transpond(l))
+ require.Equal(t, 3, l.Len())
+
+ l.Remove(l.Back())
+ require.Equal(t, []int{10, 20}, transpond(l))
+ require.Equal(t, 2, l.Len())
+
+ l.PushBack(30)
+ require.Equal(t, []int{30, 10, 20}, transpond(l))
+ require.Equal(t, 3, l.Len())
+
+ l.Remove(l.Front())
+ require.Equal(t, []int{30, 10}, transpond(l))
+ require.Equal(t, 2, l.Len())
+
+ l.PushFront(20)
+ require.Equal(t, []int{30, 10, 20}, transpond(l))
+ require.Equal(t, 3, l.Len())
for i, v := range [...]int{40, 50, 60, 70, 80} {
if i%2 == 0 {
@@ -33,19 +69,28 @@ func TestList(t *testing.T) {
} else {
l.PushBack(v)
}
- } // [80, 60, 40, 10, 30, 50, 70]
-
- require.Equal(t, l.Len(), 7)
- require.Equal(t, 80, l.Front().Value)
- require.Equal(t, 70, l.Back().Value)
-
- l.MoveToFront(l.Front()) // [80, 60, 40, 10, 30, 50, 70]
- l.MoveToFront(l.Back()) // [70, 80, 60, 40, 10, 30, 50]
-
- elems := make([]int, 0, l.Len())
- for i := l.Back(); i != nil; i = i.Next {
- elems = append(elems, i.Value.(int))
}
- require.Equal(t, []int{50, 30, 10, 40, 60, 80, 70}, elems)
+ require.Equal(t, []int{70, 50, 30, 10, 20, 40, 60, 80}, transpond(l))
+ require.Equal(t, 8, l.Len())
+
+ l.MoveToFront(l.Front())
+ require.Equal(t, []int{70, 50, 30, 10, 20, 40, 60, 80}, transpond(l))
+ require.Equal(t, 8, l.Len())
+
+ l.MoveToFront(l.Back().Next.Next) // 30
+ require.Equal(t, []int{70, 50, 10, 20, 40, 60, 80, 30}, transpond(l))
+ require.Equal(t, 8, l.Len())
+
+ l.MoveToFront(l.Back())
+ require.Equal(t, []int{50, 10, 20, 40, 60, 80, 30, 70}, transpond(l))
+ require.Equal(t, 8, l.Len())
})
}
+
+func transpond(l *List) []int {
+ elems := make([]int, 0, l.Len())
+ for i := l.Back(); i != nil; i = i.Next {
+ elems = append(elems, i.Value.(int))
+ }
+ return elems
+}
From 11d4b357743479e0650a5efbaf5536c62f7b576d Mon Sep 17 00:00:00 2001
From: Andrey Ivanov <aivanov@cinimex.ru>
Date: Tue, 23 Jun 2020 14:45:11 +0300
Subject: [PATCH 2/4] HW4 is completed
---
hw04_lru_cache/cache.go | 26 +++++++++++++++++++-------
hw04_lru_cache/cache_test.go | 7 +++----
2 files changed, 22 insertions(+), 11 deletions(-)
diff --git a/hw04_lru_cache/cache.go b/hw04_lru_cache/cache.go
index dd93cfd..1d8288e 100644
--- a/hw04_lru_cache/cache.go
+++ b/hw04_lru_cache/cache.go
@@ -1,4 +1,5 @@
package hw04_lru_cache //nolint:golint,stylecheck
+import "sync"
type Key string
@@ -12,6 +13,7 @@ type lruCache struct {
capacity int
queue *List
items map[Key]*ListItem
+ mx sync.RWMutex
}
type Item struct {
@@ -23,25 +25,33 @@ func NewCache(capacity int) Cache {
return &lruCache{
capacity: capacity,
queue: NewList(),
- items: map[Key]*ListItem{},
+ items: make(map[Key]*ListItem),
}
}
func (l *lruCache) Set(key Key, value interface{}) bool {
- if _, exists := l.Get(key); exists {
- l.items[key].Value = value
+ if _, exists := l.items[key]; exists {
+ l.mx.RLock()
+ l.items[key].Value = Item{Value: value, Key: key}
+ l.queue.MoveToFront(l.items[key])
+ l.mx.RUnlock()
return exists
}
- if l.queue.Len() >= l.capacity {
- // TODO: нужно как-то удалить элемент из мапа
- //delete(l.items,l.queue.Back().(*Item).Key)
+ if l.queue.Len() == l.capacity {
+ l.mx.RLock()
+ delete(l.items, l.queue.Back().Value.(Item).Key)
l.queue.Remove(l.queue.Back())
+ l.mx.RUnlock()
}
- l.items[key] = l.queue.PushFront(value)
+ l.mx.RLock()
+ l.items[key] = l.queue.PushFront(Item{Value: value, Key: key})
+ l.mx.RUnlock()
return false
}
func (l *lruCache) Get(key Key) (interface{}, bool) {
+ l.mx.Lock()
+ defer l.mx.Unlock()
if l.items[key] == nil {
return nil, false
}
@@ -50,7 +60,9 @@ func (l *lruCache) Get(key Key) (interface{}, bool) {
}
func (l *lruCache) Clear() {
+ l.mx.Lock()
l.items = nil
l.queue.len = 0
l.queue.Info = ListItem{}
+ l.mx.Unlock()
}
diff --git a/hw04_lru_cache/cache_test.go b/hw04_lru_cache/cache_test.go
index fd3ea5c..c16cf82 100644
--- a/hw04_lru_cache/cache_test.go
+++ b/hw04_lru_cache/cache_test.go
@@ -31,18 +31,18 @@ func TestCache(t *testing.T) {
val, ok := c.Get("aaa")
require.True(t, ok)
- require.Equal(t, 100, val)
+ require.Equal(t, 100, val.(Item).Value)
val, ok = c.Get("bbb")
require.True(t, ok)
- require.Equal(t, 200, val)
+ require.Equal(t, 200, val.(Item).Value)
wasInCache = c.Set("aaa", 300)
require.True(t, wasInCache)
val, ok = c.Get("aaa")
require.True(t, ok)
- require.Equal(t, 300, val)
+ require.Equal(t, 300, val.(Item).Value)
val, ok = c.Get("ccc")
require.False(t, ok)
@@ -79,7 +79,6 @@ func TestCache(t *testing.T) {
}
func TestCacheMultithreading(t *testing.T) {
- t.Skip() // Remove if task with asterisk completed
c := NewCache(10)
wg := &sync.WaitGroup{}
From 1db330e7123c08c9b7debcf05f4cc44cbb21db17 Mon Sep 17 00:00:00 2001
From: Andrey Ivanov <aivanov@cinimex.ru>
Date: Tue, 23 Jun 2020 15:02:08 +0300
Subject: [PATCH 3/4] HW4 is completed
---
hw04_lru_cache/cache.go | 2 +-
hw04_lru_cache/cache_test.go | 6 +++---
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/hw04_lru_cache/cache.go b/hw04_lru_cache/cache.go
index 1d8288e..e6929af 100644
--- a/hw04_lru_cache/cache.go
+++ b/hw04_lru_cache/cache.go
@@ -56,7 +56,7 @@ func (l *lruCache) Get(key Key) (interface{}, bool) {
return nil, false
}
l.queue.MoveToFront(l.items[key])
- return l.items[key].Value, true
+ return l.items[key].Value.(Item).Value, true
}
func (l *lruCache) Clear() {
diff --git a/hw04_lru_cache/cache_test.go b/hw04_lru_cache/cache_test.go
index c16cf82..09ab0bd 100644
--- a/hw04_lru_cache/cache_test.go
+++ b/hw04_lru_cache/cache_test.go
@@ -31,18 +31,18 @@ func TestCache(t *testing.T) {
val, ok := c.Get("aaa")
require.True(t, ok)
- require.Equal(t, 100, val.(Item).Value)
+ require.Equal(t, 100, val)
val, ok = c.Get("bbb")
require.True(t, ok)
- require.Equal(t, 200, val.(Item).Value)
+ require.Equal(t, 200, val)
wasInCache = c.Set("aaa", 300)
require.True(t, wasInCache)
val, ok = c.Get("aaa")
require.True(t, ok)
- require.Equal(t, 300, val.(Item).Value)
+ require.Equal(t, 300, val)
val, ok = c.Get("ccc")
require.False(t, ok)
From a161171e11b480bf7a1c7fa6261b23e25166c01f Mon Sep 17 00:00:00 2001
From: Andrey Ivanov <aivanov@cinimex.ru>
Date: Wed, 24 Jun 2020 08:29:44 +0300
Subject: [PATCH 4/4] HW4 is completed
---
hw04_lru_cache/cache.go | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/hw04_lru_cache/cache.go b/hw04_lru_cache/cache.go
index e6929af..89ec238 100644
--- a/hw04_lru_cache/cache.go
+++ b/hw04_lru_cache/cache.go
@@ -1,5 +1,8 @@
package hw04_lru_cache //nolint:golint,stylecheck
-import "sync"
+import (
+ "log"
+ "sync"
+)
type Key string
@@ -39,7 +42,11 @@ func (l *lruCache) Set(key Key, value interface{}) bool {
}
if l.queue.Len() == l.capacity {
l.mx.RLock()
- delete(l.items, l.queue.Back().Value.(Item).Key)
+ k, ok := l.queue.Back().Value.(Item)
+ if !ok {
+ log.Fatal("Ошибка приведения типов")
+ }
+ delete(l.items, k.Key)
l.queue.Remove(l.queue.Back())
l.mx.RUnlock()
}
@@ -56,7 +63,11 @@ func (l *lruCache) Get(key Key) (interface{}, bool) {
return nil, false
}
l.queue.MoveToFront(l.items[key])
- return l.items[key].Value.(Item).Value, true
+ s, ok := l.items[key].Value.(Item)
+ if !ok {
+ log.Fatal("Ошибка приведения типов")
+ }
+ return s.Value, true
}
func (l *lruCache) Clear() {