[Day13]-[动态规划]- 零钱兑换

输入：coins = [1, 2, 5], amount = 11输出：3 解释：11 = 5 + 5 + 1

输入：coins = [2], amount = 3输出：-1

输入：coins = [1], amount = 0输出：0

func coinChange(coins []int, amount int) int {	memo := map[int]float64{}	var dp func(int) float64	dp = func(n int) float64 {		if _, ok := memo[n]; ok {			return memo[n]		}		if n == 0 {			return 0		}		if n < 0 {			return -1		}		res := math.MaxFloat64		for _, coin := range coins {			subProblem := dp(n - coin)			if subProblem == -1 {				continue			}			res = math.Min(res, subProblem+1)		}
		if res == math.MaxFloat64 {			memo[n] = -1		} else {			memo[n] = res		}		// t.Log(memo)		return memo[n]	}
    return int(dp(amount))}