Add solution 189

This commit is contained in:
YDZ
2021-01-08 01:58:42 +08:00
parent c700a335cc
commit 1bc9d34209
8 changed files with 240 additions and 4 deletions

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@ -120,6 +120,8 @@
## 一. 目录
以下已经收录了 556 道题的题解,还有 13 道题在尝试优化到 beats 100%
| No. | Title | Solution | Acceptance | Difficulty | Frequency |
|:--------:|:--------------------------------------------------------------|:--------:|:--------:|:--------:|:--------:|
|0001|Two Sum|[Go](https://github.com/halfrost/LeetCode-Go/tree/master/leetcode/0001.Two-Sum)|46.1%|Easy||
@ -310,7 +312,7 @@
|0186|Reverse Words in a String II||45.0%|Medium||
|0187|Repeated DNA Sequences|[Go](https://github.com/halfrost/LeetCode-Go/tree/master/leetcode/0187.Repeated-DNA-Sequences)|41.2%|Medium||
|0188|Best Time to Buy and Sell Stock IV||29.2%|Hard||
|0189|Rotate Array||36.3%|Medium||
|0189|Rotate Array|[Go](https://github.com/halfrost/LeetCode-Go/tree/master/leetcode/0189.Rotate-Array)|36.3%|Medium||
|0190|Reverse Bits|[Go](https://github.com/halfrost/LeetCode-Go/tree/master/leetcode/0190.Reverse-Bits)|41.5%|Easy||
|0191|Number of 1 Bits|[Go](https://github.com/halfrost/LeetCode-Go/tree/master/leetcode/0191.Number-of-1-Bits)|51.8%|Easy||
|0192|Word Frequency||25.8%|Medium||

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@ -17,6 +17,8 @@ import (
"strings"
)
var try int
func main() {
var (
result []m.StatStatusPairs
@ -40,7 +42,7 @@ func main() {
// res, _ := json.Marshal(mdrows)
//writeFile("leetcode_problem", res)
mds := m.Mdrows{Mdrows: mdrows}
res, err := readFile("./template.markdown", "{{.AvailableTable}}", mds)
res, err := readFile("./template.markdown", "{{.AvailableTable}}", len(solutionIds), try, mds)
if err != nil {
fmt.Println(err)
return
@ -109,6 +111,7 @@ func loadSolutionsDir() []int {
}
}
sort.Ints(solutionIds)
try = len(files) - len(solutionIds)
fmt.Printf("读取了 %v 道题的题解,当前目录下有 %v 个文件(可能包含 .DS_Store),有 %v 道题在尝试中\n", len(solutionIds), len(files), len(files)-len(solutionIds))
return solutionIds
}
@ -153,7 +156,7 @@ func readTMPL(path string) string {
return string(data)
}
func readFile(filePath, template string, mdrows m.Mdrows) ([]byte, error) {
func readFile(filePath, template string, total, try int, mdrows m.Mdrows) ([]byte, error) {
f, err := os.OpenFile(filePath, os.O_RDONLY, 0644)
if err != nil {
return nil, err
@ -174,10 +177,14 @@ func readFile(filePath, template string, mdrows m.Mdrows) ([]byte, error) {
newByte := reg.ReplaceAll(line, []byte(mdrows.AvailableTable()))
output = append(output, newByte...)
output = append(output, []byte("\n")...)
} else if ok, _ := regexp.Match("{{.TotalNum}}", line); ok {
reg := regexp.MustCompile("{{.TotalNum}}")
newByte := reg.ReplaceAll(line, []byte(fmt.Sprintf("以下已经收录了 %v 道题的题解,还有 %v 道题在尝试优化到 beats 100%%", total, try)))
output = append(output, newByte...)
output = append(output, []byte("\n")...)
} else {
output = append(output, line...)
output = append(output, []byte("\n")...)
}
}
return output, nil
}

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@ -120,6 +120,8 @@
## 一. 目录
{{.TotalNum}}
{{.AvailableTable}}
------------------------------------------------------------------

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@ -0,0 +1,24 @@
package leetcode
// 解法一 时间复杂度 O(n),空间复杂度 O(1)
func rotate(nums []int, k int) {
k %= len(nums)
reverse(nums)
reverse(nums[:k])
reverse(nums[k:])
}
func reverse(a []int) {
for i, n := 0, len(a); i < n/2; i++ {
a[i], a[n-1-i] = a[n-1-i], a[i]
}
}
// 解法二 时间复杂度 O(n),空间复杂度 O(n)
func rotate1(nums []int, k int) {
newNums := make([]int, len(nums))
for i, v := range nums {
newNums[(i+k)%len(nums)] = v
}
copy(nums, newNums)
}

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@ -0,0 +1,50 @@
package leetcode
import (
"fmt"
"testing"
)
type question189 struct {
para189
ans189
}
// para 是参数
// one 代表第一个参数
type para189 struct {
nums []int
k int
}
// ans 是答案
// one 代表第一个答案
type ans189 struct {
one []int
}
func Test_Problem189(t *testing.T) {
qs := []question189{
{
para189{[]int{1, 2, 3, 4, 5, 6, 7}, 3},
ans189{[]int{5, 6, 7, 1, 2, 3, 4}},
},
{
para189{[]int{-1, -100, 3, 99}, 2},
ans189{[]int{3, 99, -1, -100}},
},
}
fmt.Printf("------------------------Leetcode Problem 189------------------------\n")
for _, q := range qs {
_, p := q.ans189, q.para189
fmt.Printf("【input】:%v ", p)
rotate(p.nums, p.k)
fmt.Printf("【output】:%v\n", p.nums)
}
fmt.Printf("\n\n\n")
}

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@ -0,0 +1,75 @@
# [189. Rotate Array](https://leetcode.com/problems/rotate-array/)
## 题目
Given an array, rotate the array to the right by *k* steps, where *k* is non-negative.
**Follow up:**
- Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem.
- Could you do it in-place with O(1) extra space?
**Example 1:**
```
Input: nums = [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]
```
**Example 2:**
```
Input: nums = [-1,-100,3,99], k = 2
Output: [3,99,-1,-100]
Explanation:
rotate 1 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]
```
**Constraints:**
- `1 <= nums.length <= 2 * 10^4`
- `-2^31 <= nums[i] <= 2^31 - 1`
- `0 <= k <= 10^5`
## 题目大意
给定一个数组,将数组中的元素向右移动 k 个位置,其中 k 是非负数。
## 解题思路
- 解法二,使用一个额外的数组,先将原数组下标为 i 的元素移动到 `(i+k) mod n` 的位置,再将剩下的元素拷贝回来即可。
- 解法一,由于题目要求不能使用额外的空间,所以本题最佳解法不是解法二。翻转最终态是,末尾 `k mod n` 个元素移动至了数组头部,剩下的元素右移 `k mod n` 个位置至最尾部。确定了最终态以后再变换就很容易。先将数组中所有元素从头到尾翻转一次,尾部的所有元素都到了头部,然后再将 `[0,(k mod n) 1]` 区间内的元素翻转一次,最后再将 `[k mod n, n 1]` 区间内的元素翻转一次,即可满足题目要求。
## 代码
```go
package leetcode
// 解法一 时间复杂度 O(n),空间复杂度 O(1)
func rotate(nums []int, k int) {
k %= len(nums)
reverse(nums)
reverse(nums[:k])
reverse(nums[k:])
}
func reverse(a []int) {
for i, n := 0, len(a); i < n/2; i++ {
a[i], a[n-1-i] = a[n-1-i], a[i]
}
}
// 解法二 时间复杂度 O(n),空间复杂度 O(n)
func rotate1(nums []int, k int) {
newNums := make([]int, len(nums))
for i, v := range nums {
newNums[(i+k)%len(nums)] = v
}
copy(nums, newNums)
}
```

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@ -0,0 +1,75 @@
# [189. Rotate Array](https://leetcode.com/problems/rotate-array/)
## 题目
Given an array, rotate the array to the right by *k* steps, where *k* is non-negative.
**Follow up:**
- Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem.
- Could you do it in-place with O(1) extra space?
**Example 1:**
```
Input: nums = [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]
```
**Example 2:**
```
Input: nums = [-1,-100,3,99], k = 2
Output: [3,99,-1,-100]
Explanation:
rotate 1 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]
```
**Constraints:**
- `1 <= nums.length <= 2 * 10^4`
- `-2^31 <= nums[i] <= 2^31 - 1`
- `0 <= k <= 10^5`
## 题目大意
给定一个数组,将数组中的元素向右移动 k 个位置,其中 k 是非负数。
## 解题思路
- 解法二,使用一个额外的数组,先将原数组下标为 i 的元素移动到 `(i+k) mod n` 的位置,再将剩下的元素拷贝回来即可。
- 解法一,由于题目要求不能使用额外的空间,所以本题最佳解法不是解法二。翻转最终态是,末尾 `k mod n` 个元素移动至了数组头部,剩下的元素右移 `k mod n` 个位置至最尾部。确定了最终态以后再变换就很容易。先将数组中所有元素从头到尾翻转一次,尾部的所有元素都到了头部,然后再将 `[0,(k mod n) 1]` 区间内的元素翻转一次,最后再将 `[k mod n, n 1]` 区间内的元素翻转一次,即可满足题目要求。
## 代码
```go
package leetcode
// 解法一 时间复杂度 O(n),空间复杂度 O(1)
func rotate(nums []int, k int) {
k %= len(nums)
reverse(nums)
reverse(nums[:k])
reverse(nums[k:])
}
func reverse(a []int) {
for i, n := 0, len(a); i < n/2; i++ {
a[i], a[n-1-i] = a[n-1-i], a[i]
}
}
// 解法二 时间复杂度 O(n),空间复杂度 O(n)
func rotate1(nums []int, k int) {
newNums := make([]int, len(nums))
for i, v := range nums {
newNums[(i+k)%len(nums)] = v
}
copy(nums, newNums)
}
```

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@ -168,6 +168,7 @@ headless: true
- [0174.Dungeon-Game]({{< relref "/ChapterFour/0174.Dungeon-Game.md" >}})
- [0179.Largest-Number]({{< relref "/ChapterFour/0179.Largest-Number.md" >}})
- [0187.Repeated-DNA-Sequences]({{< relref "/ChapterFour/0187.Repeated-DNA-Sequences.md" >}})
- [0189.Rotate-Array]({{< relref "/ChapterFour/0189.Rotate-Array.md" >}})
- [0190.Reverse-Bits]({{< relref "/ChapterFour/0190.Reverse-Bits.md" >}})
- [0191.Number-of-1-Bits]({{< relref "/ChapterFour/0191.Number-of-1-Bits.md" >}})
- [0198.House-Robber]({{< relref "/ChapterFour/0198.House-Robber.md" >}})