Number of unique ways that ATM can tender

An atm can only dispense values of $1, $5, $20, and $50. Return the number
of unique ways that a $ amount of X can be tendered.
($1, $5) is distinct from ($5, $1)

Input: 4 Output: 1
Input: 6 Output: 3
Input: 100 Output: 954515231698

这题和Coin Change很像，只不过这题需要考虑顺序的问题。

Solution1:

用递归做。就像斐波那契数列那样。

public int atm(int x) {if (x <= 0)return x == 0 ? 1 : 0;return atm(x - 1) + atm(x - 5) + atm(x - 20) + atm(x - 100);
}

但是这样很多重复的计算，输入太大的话会栈溢出。所以我们可以考虑把中间结果保存起来。

Solution2:

public long tellMoneyCombinations(int money) {long[] f = new long[money+1];f[0] = 1;for(int i=1; i<=money; i++) {f[i] = f[i-1];if(i>=5) f[i]+=f[i-5];if(i>=20) f[i]+=f[i-20];if(i>=50) f[i]+=f[i-50];}return f[money];
}

Number of unique ways that ATM can tender相关推荐

pandas使用nunique函数计算dataframe每个数据列的独特值的个数（count number of unique values in each column of dataframe）
pandas使用nunique函数计算dataframe每个数据列的独特值的个数(count number of unique values in each column of dataframe) ...
mysql unique count_MySQL - Count Number of Unique Values
问题 If I have three columns: orderNumber, name, email and I would like to count how many unique email ...
Dollar Dayz POJ - 3181（动态规划+大数高低位分离输出）
题意:就是给出二个数N,和k,有1~k种钱币,每种都是无限个,用这些种类的钱币可以组合成总钱N有多少种方式. 解题:这就是一个完全背包,把N看成容量,钱币的类型值为花费和价值.与记录有多少种路径的 ...
插图引用同一行两个插图_数学身份的优雅LED插图
插图引用同一行两个插图 by Chris Lam 克里斯·林(Chris Lam) 数学身份的优雅LED插图 (An elegant LED illustration of a mathemati ...
UVA10338 Mischievous Children【组合数学】
Adam's parents put up a sign that says "CONGRATULATIONS". The sign is so big that exactly ...
bzoj 1655: [Usaco2006 Jan] Dollar Dayz 奶牛商店（高精度完全背包）
1655: [Usaco2006 Jan] Dollar Dayz 奶牛商店 Time Limit: 5 Sec Memory Limit: 64 MB Submit: 599 Solved: 3 ...
Dollar Dayz-完全背包+大数处理
[题目] Farmer John goes to Dollar Days at The Cow Store and discovers an unlimited number of tools on ...
leetcode63. Unique Paths II
题目要求 Follow up for "Unique Paths":Now consider if some obstacles are added to the grids. H ...
Unique Paths II leetcode java
题目: Follow up for "Unique Paths": Now consider if some obstacles are added to the grids. H ...

Number of unique ways that ATM can tender

Number of unique ways that ATM can tender相关推荐

最新文章

热门文章