322.零钱兑换.java

/*
 * @lc app=leetcode.cn id=322 lang=java
 *
 * [322] 零钱兑换
 */

// @lc code=start

import java.util.Arrays;

class Solution {
    public int coinChange(int[] coins, int amount) {
        // this is leetcode official solution's method
        int[] dp = new int[amount + 1];
        for (int i = 1; i < dp.length; i++) {
            dp[i] = amount + 1;
            for (int j = 0; j < coins.length; j++) {
                if (i - coins[j] >= 0) {
                    dp[i] = Math.min(dp[i], dp[i - coins[j]] + 1);
                }
            }
        }

        return dp[amount] == amount + 1 ? -1 : dp[amount];
    }
}
// @lc code=end