[LeetCode] Coin Change

Wrong one with greedy way,
Example: [130, 110, 1] 220

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public class Solution {     public int coinChange(int[] coins, int amount) {         if (coins == null || coins.length == 0) return -1;         Arrays.sort(coins);         return numberOfCoins(coins, coins.length - 1, amount);     }          private int numberOfCoins(int[] coins, int coinIndex, int remainAmount) {         if (remainAmount == 0) return 0;         if (coinIndex < 0) return -1;         int numberOfCurrentCoin = remainAmount / coins[coinIndex];         while (numberOfCurrentCoin >= 0) {             int numberOfRemainCoin = numberOfCoins(coins, coinIndex-1, remainAmount - numberOfCurrentCoin * coins[coinIndex]);             if (numberOfRemainCoin >= 0) return numberOfRemainCoin + numberOfCurrentCoin;             numberOfCurrentCoin--;         }         return -1;     } }

Iterative solution:
https://leetcode.com/discuss/76217/java-both-iterative-recursive-solutions-with-explanations

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public class Solution {     public int coinChange(int[] coins, int amount) {         if (coins == null || coins.length == 0) return -1;         if (amount <= 0) return 0;                  int[] minCoins = new int[amount + 1];         minCoins[0] = 0;                  for (int i = 1; i <= amount; i++) {             minCoins[i] = Integer.MAX_VALUE;             for (int coin : coins) {                 if (i - coin >= 0 && minCoins[i - coin] != Integer.MAX_VALUE) {                     minCoins[i] = Math.min(minCoins[i], minCoins[i - coin] + 1);                 }             }         }                  return minCoins[amount] == Integer.MAX_VALUE ? -1 : minCoins[amount];     } }

Recursive solution:

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public class Solution {     public int coinChange(int[] coins, int amount) {         if (coins == null || coins.length == 0) return -1;         if (amount <= 0) return 0;         HashMap<Integer, Integer> amountToCoinNumber = new HashMap<Integer, Integer>();         return coinChangeHelper(coins, amount, amountToCoinNumber);     }           private int coinChangeHelper(int[] coins, int amount, HashMap<Integer, Integer> amountToCoinNumber){         if (amount == 0) return 0;         if (amount < 0) return -1;         if (amountToCoinNumber.containsKey(amount)) return amountToCoinNumber.get(amount);         int minimumNumber = -1;         for (int coin : coins) {             int remainNumber = coinChangeHelper(coins, amount - coin, amountToCoinNumber);             if (remainNumber >= 0) {                 minimumNumber = Math.min(minimumNumber == - 1 ? Integer.MAX_VALUE : minimumNumber , remainNumber + 1);             }         }         amountToCoinNumber.put(amount, minimumNumber);         return amountToCoinNumber.get(amount);     } }