P2871 [USACO07DEC]手链Charm Bracelet(01背包模板)
题目传送门:P2871 [USACO07DEC]手链Charm Bracelet
题目描述
Bessie has gone to the mall's jewelry store and spies a charm bracelet. Of course, she'd like to fill it with the best charms possible from the N (1 ≤ N ≤ 3,402) available charms. Each charm i in the supplied list has a weight Wi (1 ≤ Wi ≤ 400), a 'desirability' factor Di (1 ≤ Di ≤ 100), and can be used at most once. Bessie can only support a charm bracelet whose weight is no more than M (1 ≤ M ≤ 12,880).
Given that weight limit as a constraint and a list of the charms with their weights and desirability rating, deduce the maximum possible sum of ratings.
有N件物品和一个容量为V的背包。第i件物品的重量是c[i],价值是w[i]。求解将哪些物品装入背包可使这些物品的重量总和不超过背包容量,且价值总和最大。
输入输出格式
输入格式:
* Line 1: Two space-separated integers: N and M
* Lines 2..N+1: Line i+1 describes charm i with two space-separated integers: Wi and Di
第一行:物品个数N和背包大小M
第二行至第N+1行:第i个物品的重量C[i]和价值W[i]
输出格式:
* Line 1: A single integer that is the greatest sum of charm desirabilities that can be achieved given the weight constraints
输出一行最大价值。
输入输出样例
23
题解:
01背包模板题。
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#include<bits/stdc++.h> using namespace std; const int N = 3410; const int M = 13000; int c[N],w[N],dp[M]={0}; int main() { int n,m; scanf("%d%d",&n,&m); for (int i=1;i<=n;i++) scanf("%d%d",&c[i],&w[i]); for (int i=1;i<=n;i++) for (int j=m;j>=c[i];j--) dp[j]=max(dp[j],dp[j-c[i]]+w[i]); printf("%d\n",dp[m]); return 0; } 01背包