题目链接 题意: 亮亮有N个有瑕疵的硬币,有瑕疵意味着抛一枚硬币正面向上的概率 不等于 反面向上的概率 也即概率不等于0.5. 现在亮亮一次抛N个硬币 , 恰好有K个硬币正面向上 ,接着他又想抛一次 , 问:出现正面向上的个数的期望 抛硬币这个随机实验满足二项分布,即X~B(p , N) 所以期望 E(X) = N * P 而正面向上的概率不定 , 则概率为r的期望为: 即:E[X] = N * E[r]. 接下来对E[r]进行化简: ∵p~Be(K+1 , N-K+1) 代入原式得:E(x)=…

题目链接: Lightoj  1231 - Coin Change (I) 题目描述: 就是有n种硬币,每种硬币有两个属性(价值,数目).问用给定的硬币组成K面值,有多少种方案? 解题思路: 赤果果的多重背包,简单搞一下就好了.席八!烦烦烦.今天绝对是出门刷提前没看黄历,刚开始套了一个多重背包板子,蓝而跑出来的答案并不对,改来改去就错在细节的地方. #include <cmath> #include <cstdio> #include <cstring> #includ…

先上题目: 1231 - Coin Change (I)   PDF (English) Statistics Forum Time Limit: 1 second(s) Memory Limit: 32 MB In a strange shop there are n types of coins of value A1, A2 ... An. C1, C2, ... Cn denote the number of coins of value A1, A2 ... An respective…

免费做一样新 1004 - Monkey Banana Problem 号码塔 1005 - Rooks 排列 1013 - Love Calculator LCS变形 dp[i][j][k]对于第一个字符串i 到jLCS为k的方案数 1068 - Investigation 数位dp 能被K整数且各位数字之和也能被K整除的数 dp[i][j][k] 到第i位每位数字之和的余数为j 当前数字余数为k 1079 - Just another Robbery 01背包 全部钱之和为背包体积 不被抓的…

UVA 674  Coin Change  解题报告 题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87730#problem/E 题目: Suppose there are 5 types of coins: 50-cent, 25-cent, 10-cent, 5-cent, and 1-cent. We want to make changes with these coins for a given amount o…

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,…

题目描述 Farmer John's cows like to play coin games so FJ has invented with a new two-player coin game called Xoinc for them. Initially a stack of N (5 <= N <= 2,000) coins sits on the ground; coin i from the top has integer value C_i (1 <= C_i <=…

题目描述 Farmer John's cows like to play coin games so FJ has invented with a new two-player coin game called Xoinc for them. Initially a stack of N (5 <= N <= 2,000) coins sits on the ground; coin i from the top has integer value C_i (1 <= C_i <=…

原题链接在这里:https://leetcode.com/problems/coin-change/ 题目: 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 m…

1017 - Exact cover 时间限制:15秒 内存限制:128兆 自定评测 5584 次提交 2975 次通过 题目描述 There is an N*M matrix with only 0s and 1s, (1 <= N,M <= 1000). An exact cover is a selection of rows such that every column has a 1 in exactly one of the selected rows. Try to find o…