Merge pull request #484 from jojoo15/patch-38

增加 0188 买股票的最佳时机IV python3版本二

problems/0188.买卖股票的最佳时机IV.md

@@ -224,7 +224,7 @@ class Solution {
 
 
 Python：
-
+版本一
 ```python
 class Solution:
     def maxProfit(self, k: int, prices: List[int]) -> int:
@@ -239,7 +239,22 @@ class Solution:
                 dp[i][j+2] = max(dp[i-1][j+2], dp[i-1][j+1] + prices[i])
         return dp[-1][2*k]
 ```
-
+版本二
+```python3
+class Solution:
+    def maxProfit(self, k: int, prices: List[int]) -> int:
+        if len(prices) == 0: return 0
+        dp = [0] * (2*k + 1)
+        for i in range(1,2*k,2):
+            dp[i] = -prices[0]
+        for i in range(1,len(prices)):
+            for j in range(1,2*k + 1):
+                if j % 2:
+                    dp[j] = max(dp[j],dp[j-1]-prices[i])
+                else:
+                    dp[j] = max(dp[j],dp[j-1]+prices[i])
+        return dp[2*k]
+```
 Go：