poj 3624Charm Bracelet(简单01背包)

              这是一道水的不能再水的题了，不过，不用空间优化的话，会超内存的……

Charm Bracelet

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 10038		Accepted: 4511

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 W_i (1 ≤ W_i ≤ 400), a 'desirability' factor D_i (1 ≤ D_i ≤ 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: W_i and D_i

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

#include<iostream>
using namespace std;
int a[12881]={0};
int main()
{
   int n, m;
   int w[3403], d[3403];
   cin>>n>>m;
   int i, j;
   for(i=1; i<=n; i++)
        cin>>w[i]>>d[i];
   for(i=1; i<=n; i++)
       for(j=m; j>=w[i]; j--)
       {
           if(  a[j]<a[j-w[i]]+d[i])
                 a[j]=a[j-w[i]]+d[i];
       }
    cout<<a[m]<<endl;
}