Update 0377.组合总和Ⅳ.md

problems/0377.组合总和Ⅳ.md

@@ -175,22 +175,36 @@ class Solution {
 ```
 
 Python：
+卡哥版
+```python
+class Solution:
+    def combinationSum4(self, nums: List[int], target: int) -> int:
+        dp = [0] * (target + 1)
+        dp[0] = 1
+        for i in range(1, target + 1):  # 遍历背包
+            for j in range(len(nums)):  # 遍历物品
+                if i - nums[j] >= 0:
+                    dp[i] += dp[i - nums[j]]
+        return dp[target]
+
+```
+优化版
 
 ```python
 class Solution:
-    def combinationSum4(self, nums, target):
+    def combinationSum4(self, nums: List[int], target: int) -> int:
-        dp = [0] * (target + 1)
+        dp = [0] * (target + 1)  # 创建动态规划数组，用于存储组合总数
-        dp[0] = 1
+        dp[0] = 1  # 初始化背包容量为0时的组合总数为1
+
+        for i in range(1, target + 1):  # 遍历背包容量
+            for j in nums:  # 遍历物品列表
+                if i >= j:  # 当背包容量大于等于当前物品重量时
+                    dp[i] += dp[i - j]  # 更新组合总数
+
+        return dp[-1]  # 返回背包容量为target时的组合总数
 
-        for i in range(1, target+1):
-            for j in nums:
-                if i >= j:
-                    dp[i] += dp[i - j]
 
-        return dp[-1]
 ```
-
-
 Go：
 ```go
 func combinationSum4(nums []int, target int) int {