added Coin Change DP

Author: minhyeong-joe

DynamicProgramming/CoinChange/README.md

@@ -0,0 +1,38 @@
+# Coin Change
+
+[Leetcode Link](https://leetcode.com/problems/coin-change/)
+
+## Problem:
+
+You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you need to make up that amount. If that amount of money cannot be made up by any combination of the coins, return -1.
+
+You may assume that you have an infinite number of each kind of coin.
+
+## Example:
+
+```
+Input: coins = [1,2,5], amount = 11
+Output: 3
+Explanation: 11 = 5 + 5 + 1
+```
+
+```
+Input: coins = [2], amount = 3
+Output: -1
+```
+
+```
+Input: coins = [1], amount = 0
+Output: 0
+```
+
+```
+Input: coins = [1], amount = 1
+Output: 1
+```
+
+## Note:
+
+- 1 <= coins.length <= 12
+- 1 <= coins[i] <= 231 - 1
+- 0 <= amount <= 104

DynamicProgramming/CoinChange/solution.py

@@ -0,0 +1,19 @@
+from typing import List
+
+
+class Solution:
+    def coinChange(self, coins: List[int], amount: int) -> int:
+        dp = [float('inf') for _ in range(amount+1)]
+        dp[0] = 0
+        for coin in coins:
+            for amt in range(1, amount+1):
+                if coin <= amt:
+                    dp[amt] = min(dp[amt], 1 + dp[amt - coin])
+            print(dp)
+        return dp[-1] if dp[-1] != float('inf') else -1
+
+
+sol = Solution()
+coins = [1, 2, 5]
+amount = 11
+print(sol.coinChange(coins, amount))

README.md

@@ -59,6 +59,7 @@ Languages used: Java and Python
 ### [Dynamic Programming](./DynamicProgramming)
 
 - [Climbing Stairs](DynamicProgramming/ClimbingStairs)
+- [Coin Change](DynamicProgramming/CoinChange)
 - [Count Square With Ones](DynamicProgramming/CountSquareWithOnes)
 - [House Robber](DynamicProgramming/HouseRobber)
 - [Longest Increasing Subsequence](DynamicProgramming/LongestIncreasingSubsequence)