优化

problems/0322.零钱兑换.md

@@ -209,19 +209,19 @@ class Solution:
     def coinChange(self, coins: List[int], amount: int) -> int:
         '''版本一'''
         # 初始化
-        dp = [amount + 1]*(amount + 1)
+        dp = [float("inf")]*(amount + 1)
         dp[0] = 0
         # 遍历物品
         for coin in coins:
             # 遍历背包
             for j in range(coin, amount + 1):
                 dp[j] = min(dp[j], dp[j - coin] + 1)
-        return dp[amount] if dp[amount] < amount + 1 else -1
+        return dp[amount] if dp[amount] != float("inf") else -1
 
     def coinChange1(self, coins: List[int], amount: int) -> int:
         '''版本二'''
         # 初始化
-        dp = [amount + 1]*(amount + 1)
+        dp = [float("inf")]*(amount + 1)
         dp[0] = 0
         # 遍历物品
         for j in range(1, amount + 1):
@@ -229,7 +229,7 @@ class Solution:
             for coin in coins:
                 if j >= coin:
                 	dp[j] = min(dp[j], dp[j - coin] + 1)
-        return dp[amount] if dp[amount] < amount + 1 else -1
+        return dp[amount] if dp[amount] != float("inf") else -1
 ```