coin dp问题

Author: genkimaru

src/dynamicplan/coin.py

@@ -0,0 +1,37 @@
+from typing import List
+
+class Solution:
+    def coinChange(self, coins: List[int], amount: int) -> int:
+        if amount == 0:
+            return 0
+        
+        ## 去掉大于amount的 coins
+        coins = list(filter(lambda x : x <= amount , coins ))
+        if not coins:
+            return -1
+        if amount < min(coins):
+            return -1
+
+        ## 初始化dp
+        dp = [ 0 ] *( amount+ 1)
+
+        for i in coins:
+            dp[i] = 1
+
+        dp[1:min(coins)] = [ float('inf') ] * (min(coins) - 1)
+
+        for i in range(min(coins) , amount+1):
+            min_count = float('inf')
+            j = i 
+            while j <= i and j >= min(coins):
+                if j in coins :
+                    min_count = min(min_count , 1 + dp[i - j])
+                j -= 1
+            dp[i] = min_count
+
+        return dp[amount] if dp[amount] != float('inf') else -1 
+
+coins = [1,2,5]
+amount = 11
+print(Solution().coinChange(coins, amount))
+