Coin Change Better Solution (DP)

Author: nirmalnishant645

0322-Coin-Change.py

@@ -47,4 +47,19 @@ def coinChange(self, coins: List[int], amount: int) -> int:
  for j in range(len(coins)):
  if coins[j] <= i:
  dp[i] = min(dp[i], 1 + dp[i - coins[j]])
+ return -1 if dp[amount] > amount else dp[amount]
+
+# Slightly optimised for average case
+
+class Solution:
+ def coinChange(self, coins: List[int], amount: int) -> int:
+ coins.sort()
+ dp = [amount + 1 for _ in range(amount + 1)]
+ dp[0] = 0
+ for i in range(amount + 1):
+ for j in range(len(coins)):
+ if coins[j] <= i:
+ dp[i] = min(dp[i], 1 + dp[i - coins[j]])
+ else:
+ break
  return -1 if dp[amount] > amount else dp[amount]