风华是一指流砂,苍老是一段年华。
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.
输入
* 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
输出
* Line 1: A single integer that is the greatest sum of charm desirabilities that can be achieved given the weight constraints
样例输入
copy
4 6 1 4 2 6 3 12 2 7
样例输出
23
提示
01背包问题,需要使用滚动数组进行优化,不然内存超限。
#include<cstdio>
#include<iostream>
#include<cmath>
using namespace std;
int w[3500],d[3500],ml[13000];
int main()
{
int he,m,n,i,j;
scanf("%d",&n);
scanf("%d",&m);
for(i=0;i<n;i++)
{
scanf("%d",&w[i]);
scanf("%d",&d[i]);
}
for(i=0;i<n;i++)
{
for(j=m;j>0;j--)
{
//if(w[i]<=j&&ml[j-w[i]]+d[i]>ml[j])
// ml[j]=ml[j-w[i]]+d[i];
if(w[i]<=j)
ml[j]=max(ml[j-w[i]]+d[i],ml[j]);
}
}
he=0;
for(i=0;i<=m;i++)
he=max(he,ml[i]);
cout<<he<<endl;
return 0;
}