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Update 0376.摆动序列.md
按着讲解的原理,分别完善了Golang版本的贪心算法和动态规划算法。
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@ -266,22 +266,58 @@ class Solution:
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### Go
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**贪心**
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```golang
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func wiggleMaxLength(nums []int) int {
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var count,preDiff,curDiff int
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count=1
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if len(nums)<2{
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return count
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}
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for i:=0;i<len(nums)-1;i++{
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curDiff=nums[i+1]-nums[i]
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//如果有正有负则更新下标值||或者只有前一个元素为0(针对两个不等元素的序列也视作摆动序列,且摆动长度为2)
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if (curDiff > 0 && preDiff <= 0) || (preDiff >= 0 && curDiff < 0){
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preDiff=curDiff
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count++
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}
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}
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return count
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var count, preDiff, curDiff int //初始化默认为0
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count = 1 // 初始化为1,因为最小的序列是1个数
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if len(nums) < 2 {
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return count
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}
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for i := 0; i < len(nums)-1; i++ {
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curDiff = nums[i+1] - nums[i]
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if (curDiff > 0 && preDiff <= 0) || (curDiff < 0 && preDiff >= 0) {
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count++
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}
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}
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return count
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}
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```
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**动态规划**
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```golang
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func wiggleMaxLength(nums []int) int {
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n := len(nums)
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if n <= 1 {
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return n
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}
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dp := make([][2]int, n)
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// i 0 作为波峰的最大长度
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// i 1 作为波谷的最大长度
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dp[0][0] = 1
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dp[0][1] = 1
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for i := 0; i < n; i++ {
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for j := 0; j < i; j++ {
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if nums[j] > nums[i] { //nums[i]为波谷
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dp[i][1] = max(dp[i][1], dp[j][0]+1)
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}
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if nums[j] < nums[i] { //nums[i]为波峰 或者相等
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dp[i][0] = max(dp[i][0], dp[j][1]+1)
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}
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if nums[j] == nums[i] { //添加一种情况,nums[i]为相等
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dp[i][0] = max(dp[i][0], dp[j][0]) //波峰
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dp[i][1] = max(dp[i][1], dp[j][1]) //波谷
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}
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}
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}
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return max(dp[n-1][0], dp[n-1][1])
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}
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func max(a, b int) int {
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if a > b {
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return a
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} else {
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return b
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}
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}
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```
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