Poj3624 Charm Bracelet (01背包)

题目链接:http://poj.org/problem?id=3624

Description

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.

Input

* 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

Output

* Line 1: A single integer that is the greatest sum of charm desirabilities that can be achieved given the weight constraints

Sample Input

4 6
1 4
2 6
3 12
2 7

Sample Output

23

Source

 
二维dp数组会超内存,得使用优化后的一维dp数组
 1 #include <iostream>
 2 #include <algorithm>
 3 using namespace std;
 4 int n,m;
 5 int v[3500];
 6 int w[3500];
 7 int dp[13000];
 8 int main()
 9 {
10     while(cin>>n>>m){
11         for(int i=0;i<n;i++){
12             cin>>w[i]>>v[i];
13         }
14         for(int i=0;i<n;i++){
15             for(int j=m;j>=w[i];j--){
16                 dp[j]=max(dp[j],dp[j-w[i]]+v[i]);
17             }
18         }
19         cout<<dp[m]<<endl;
20     }
21     return 0;
22 } 

 

posted @ 2019-03-22 14:38  wydxry  阅读(295)  评论(0编辑  收藏  举报
Live2D