hdu 2844 poj 1742 Coins 题目相同,但是时限不同,原本上面的多重背包我初始化为0,f[0] = 1;用位或进行优化,f[i]=1表示可以兑成i,0表示不能. 在poj上运行时间正好为时限3000ms....太慢了,hdu直接TLE(时限1s); 之 后发现其实并不是算法的问题,而是库函数的效率没有关注到.我是使用fill()按量初始化的,但是由于memset()可能是系统底层使用了四个字节拷 贝的函数(远比循环初始化快),效率要高得多..这就是为什么一直TLE的原因,fil…

Problem Description Whuacmers use coins.They have coins of value A1,A2,A3...An Silverland dollar. One day Hibix opened purse and found there were some coins. He decided to buy a very nice watch in a nearby shop. He wanted to pay the exact price(witho…

Description People in Silverland use coins.They have coins of value A1,A2,A3...An Silverland dollar.One day Tony opened his money-box and found there were some coins.He decided to buy a very nice watch in a nearby shop. He wanted to pay the exact pri…

Coins Time Limit: 3000MS   Memory Limit: 30000K Total Submissions: 28448   Accepted: 9645 Description People in Silverland use coins.They have coins of value A1,A2,A3...An Silverland dollar.One day Tony opened his money-box and found there were some…

Coins HDU - 2844 POJ - 1742 多重背包可行性 当做一般多重背包,二进制优化 #include<cstdio> #include<cstring> int n,m,anss; ],c[],f[]; int main() { int i,j,t; scanf("%d%d",&n,&m); ||m!=) { anss=; memset(f,,sizeof(f)); ;i<=n;i++) scanf("%d&qu…

Coins Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 11596    Accepted Submission(s): 4634 Problem Description Whuacmers use coins.They have coins of value A1,A2,A3...An Silverland dollar. One…

题意:给你N个种硬币,价值和数量,知道手表不大于m,问能组成(1~m)的价格有多少种情况 套套上次那题的模板直接就行了,http://blog.csdn.net/neng18/article/details/17060539 #include <iostream> #include<cstring> #include<cstdio> using namespace std; #define MAXV 150 #define MAXM 100050 int cash,n,…

POJ 3260 The Fewest Coins(多重背包+全然背包) http://poj.org/problem?id=3260 题意: John要去买价值为m的商品. 如今的货币系统有n种货币,相应面值为val[1],val[2]-val[n]. 然后他身上每种货币有num[i]个. John必须付给售货员>=m的金钱, 然后售货员会用最少的货币数量找钱给John. 问你John的交易过程中, 他给售货员的货币数目+售货员找钱给他的货币数目 的和最小值是多少? 分析: 本题与POJ 12…

HDU 3732 Ahui Writes Word(多重背包) http://acm.hdu.edu.cn/showproblem.php? pid=3732 题意: 初始有N个物品, 每一个物品有cost[i]花费和val[i]价值, 你有m元钱, 如今问你最多能买多少总价值的物品? 当中N<=10W, m<=1W. 且cost[i]和val[i]都在[0,10]范围. 分析: 本题初看直接用01背包来做是直观的想法. 可是考虑到01背包的复杂度为O(N*m), 这么大的复杂度肯定不行. 然…

http://poj.org/problem?id=1742 n个硬币,面值分别是A1...An,对应的数量分别是C1....Cn.用这些硬币组合起来能得到多少种面值不超过m的方案. 多重背包,不过这题很容易超时,用背包九讲的代码有人说行,但是我提交还是超时,后来参考别人代码加了一些优化才能过,有时间要去搞清楚多重背包的单调队列优化. #include<cstdio> #include<cstring> #include<algorithm> using namespa…