Merge pull request 6boris#110 from kylesliu/develop

Develop

Author: 6boris

README.md

@@ -3,8 +3,8 @@
 LeetCode of algorithms with golang solution(updating:smiley:).
 
 <p align="center">
-    <img src="http://s.gin.sh/logo/golang-3.png">
-    <img src="http://s.gin.sh/logo/leetcode-2.png">
+    <img src="https://s.gin.sh/logo/go/PNG/Go-Logo_Aqua.png" width="160" height="130">
+    <img src="http://s.gin.sh/logo/leetcode.png" width="250" height="130">
 </p>
 
 <p align="center">

lib/lru/lru.go

@@ -0,0 +1,79 @@
+package lru
+
+import "container/list"
+
+// Cache is a LRU cache. It is not safe for concurrent access.
+type Cache struct {
+	maxBytes int64
+	nbytes   int64
+	ll       *list.List
+	cache    map[string]*list.Element
+	// optional and executed when an entry is purged.
+	OnEvicted func(key string, value Value)
+}
+
+type entry struct {
+	key   string
+	value Value
+}
+
+// Value use Len to count how many bytes it takes
+type Value interface {
+	Len() int
+}
+
+// New is the Constructor of Cache
+func New(maxBytes int64, onEvicted func(string, Value)) *Cache {
+	return &Cache{
+		maxBytes:  maxBytes,
+		ll:        list.New(),
+		cache:     make(map[string]*list.Element),
+		OnEvicted: onEvicted,
+	}
+}
+
+// Add adds a value to the cache.
+func (c *Cache) Add(key string, value Value) {
+	if ele, ok := c.cache[key]; ok {
+		c.ll.MoveToFront(ele)
+		kv := ele.Value.(*entry)
+		kv.value = value
+		return
+	}
+	ele := c.ll.PushFront(&entry{key, value})
+	c.cache[key] = ele
+	c.nbytes += int64(len(key)) + int64(value.Len())
+
+	for c.maxBytes != 0 && c.maxBytes < c.nbytes {
+		c.RemoveOldest()
+	}
+}
+
+// Get look ups a key's value
+func (c *Cache) Get(key string) (value Value, ok bool) {
+	if ele, ok := c.cache[key]; ok {
+		c.ll.MoveToFront(ele)
+		kv := ele.Value.(*entry)
+		return kv.value, true
+	}
+	return
+}
+
+// RemoveOldest removes the oldest item
+func (c *Cache) RemoveOldest() {
+	ele := c.ll.Back()
+	if ele != nil {
+		c.ll.Remove(ele)
+		kv := ele.Value.(*entry)
+		delete(c.cache, kv.key)
+		c.nbytes -= int64(len(kv.key)) + int64(kv.value.Len())
+		if c.OnEvicted != nil {
+			c.OnEvicted(kv.key, kv.value)
+		}
+	}
+}
+
+// Len the number of cache entries
+func (c *Cache) Len() int {
+	return c.ll.Len()
+}

lib/lru/lru_test.go

@@ -0,0 +1,55 @@
+package lru
+
+import (
+	"reflect"
+	"testing"
+)
+
+type String string
+
+func (d String) Len() int {
+	return len(d)
+}
+
+func TestGet(t *testing.T) {
+	lru := New(int64(0), nil)
+	lru.Add("key1", String("1234"))
+	if v, ok := lru.Get("key1"); !ok || string(v.(String)) != "1234" {
+		t.Fatalf("cache hit key1=1234 failed")
+	}
+	if _, ok := lru.Get("key2"); ok {
+		t.Fatalf("cache miss key2 failed")
+	}
+}
+
+func TestRemoveoldest(t *testing.T) {
+	k1, k2, k3 := "key1", "key2", "k3"
+	v1, v2, v3 := "value1", "value2", "v3"
+	cap := len(k1 + k2 + v1 + v2)
+	lru := New(int64(cap), nil)
+	lru.Add(k1, String(v1))
+	lru.Add(k2, String(v2))
+	lru.Add(k3, String(v3))
+
+	if _, ok := lru.Get("key1"); ok || lru.Len() != 2 {
+		t.Fatalf("Removeoldest key1 failed")
+	}
+}
+
+func TestOnEvicted(t *testing.T) {
+	keys := make([]string, 0)
+	callback := func(key string, value Value) {
+		keys = append(keys, key)
+	}
+	lru := New(int64(10), callback)
+	lru.Add("key1", String("123456"))
+	lru.Add("k2", String("k2"))
+	lru.Add("k3", String("k3"))
+	lru.Add("k4", String("k4"))
+
+	expect := []string{"key1", "k2"}
+
+	if !reflect.DeepEqual(expect, keys) {
+		t.Fatalf("Call OnEvicted failed, expect keys equals to %s", expect)
+	}
+}

src/0241.Different-Ways-to-Add-Parentheses/README.md

@@ -0,0 +1,48 @@
+# [241. Different Ways to Add Parentheses][title]
+
+## Description
+
+Given two binary strings, return their sum (also a binary string).
+
+The input strings are both **non-empty** and contains only characters `1` or `0`.
+
+**Example 1:**
+
+```
+Input: a = "11", b = "1"
+Output: "100"
+```
+
+**Example 2:**
+
+```
+Input: a = "1010", b = "1011"
+Output: "10101"
+```
+
+**Tags:** Math, String
+
+## 题意
+> 求2数之和
+
+## 题解
+
+### 思路1
+> 。。。。
+
+```go
+
+```
+
+### 思路2
+> 思路2
+```go
+
+```
+
+## 结语
+
+如果你同我一样热爱数据结构、算法、LeetCode，可以关注我 GitHub 上的 LeetCode 题解：[awesome-golang-leetcode][me]
+
+[title]: https://leetcode.com/problems/different-ways-to-add-parentheses/
+[me]: https://github.com/kylesliu/awesome-golang-leetcode

src/0241.Different-Ways-to-Add-Parentheses/Solution.go

@@ -0,0 +1,5 @@
+package Solution
+
+func diffWaysToCompute(input string) []int {
+	return []int{}
+}

src/0241.Different-Ways-to-Add-Parentheses/Solution_test.go

@@ -0,0 +1,40 @@
+package Solution
+
+import (
+	"reflect"
+	"strconv"
+	"testing"
+)
+
+func TestSolution(t *testing.T) {
+	//	测试用例
+	cases := []struct {
+		name   string
+		inputs string
+		expect []int
+	}{
+		{"TestCase", "2-1-1", []int{0, 2}},
+		{"TestCase", "2*3-4*5", []int{-34, -14, -10, -10, 10}},
+	}
+
+	//	开始测试
+	for i, c := range cases {
+		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
+			got := diffWaysToCompute(c.inputs)
+			if !reflect.DeepEqual(got, c.expect) {
+				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
+					c.expect, got, c.inputs)
+			}
+		})
+	}
+}
+
+//	压力测试
+func BenchmarkSolution(b *testing.B) {
+
+}
+
+//	使用案列
+func ExampleSolution() {
+
+}

src/0409.Longest-Palindrome/README.md

@@ -0,0 +1,53 @@
+# [409. Longest Palindrome][title]
+
+## Description
+
+Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters.
+
+This is case sensitive, for example "Aa" is not considered a palindrome here.
+
+Note:
+Assume the length of given string will not exceed 1,010.
+
+**Example 1:**
+
+```
+Input:
+"abccccdd"
+
+Output:
+7
+
+Explanation:
+One longest palindrome that can be built is "dccaccd", whose length is 7.
+```
+
+**Tags:** Math, String
+
+## 题意
+> 求2数之和
+
+## 题解
+
+### 思路1
+> 用哈希表统计每个字符出现的次数
+  判断奇偶性：
+  若字符出现次数为偶数，则肯定能够组成回文串，计入累加器
+  若为奇数，添加个数-1并计入累加器，并且标记存在中心字符
+
+```go
+
+```
+
+### 思路2
+> 思路2
+```go
+
+```
+
+## 结语
+
+如果你同我一样热爱数据结构、算法、LeetCode，可以关注我 GitHub 上的 LeetCode 题解：[awesome-golang-leetcode][me]
+
+[title]: https://leetcode.com/problems/longest-palindrome/
+[me]: https://github.com/kylesliu/awesome-golang-leetcode

src/0409.Longest-Palindrome/Solution.go

@@ -0,0 +1,20 @@
+package Solution
+
+func longestPalindrome(s string) int {
+	m, ans, has_odd := make(map[rune]int, 128), 0, false
+	for _, v := range s {
+		m[v]++
+	}
+	for _, v := range m {
+		ans += v
+		if v%2 == 1 {
+			ans--
+			has_odd = true
+		}
+	}
+	if has_odd {
+		ans++
+	}
+
+	return ans
+}

src/0409.Longest-Palindrome/Solution_test.go

@@ -0,0 +1,39 @@
+package Solution
+
+import (
+	"reflect"
+	"strconv"
+	"testing"
+)
+
+func TestSolution(t *testing.T) {
+	//	测试用例
+	cases := []struct {
+		name   string
+		inputs string
+		expect int
+	}{
+		{"TestCase", "abccccdd", 7},
+	}
+
+	//	开始测试
+	for i, c := range cases {
+		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
+			got := longestPalindrome(c.inputs)
+			if !reflect.DeepEqual(got, c.expect) {
+				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
+					c.expect, got, c.inputs)
+			}
+		})
+	}
+}
+
+//	压力测试
+func BenchmarkSolution(b *testing.B) {
+
+}
+
+//	使用案列
+func ExampleSolution() {
+
+}