## hdu2639Bone Collector II (01背包，求第k优解)

2018年02月22日 ⁄ 综合 ⁄ 共 1966字 ⁄ 字号 评论关闭
Problem Description
The title of this problem is familiar,isn't it?yeah,if you had took part in the "Rookie Cup" competition,you must have seem this title.If you haven't seen it before,it doesn't matter,I will give you a link:

Today we are not desiring the maximum value of bones,but the K-th maximum value of the bones.NOTICE that,we considerate two ways that get the same value of bones are the same.That means,it will be a strictly decreasing sequence from
the 1st maximum , 2nd maximum .. to the K-th maximum.

If the total number of different values is less than K,just ouput 0.

Input
The first line contain a integer T , the number of cases.
Followed by T cases , each case three lines , the first line contain two integer N , V, K(N <= 100 , V <= 1000 , K <= 30)representing the number of bones and the volume of his bag and the K we need. And the second line contain N integers representing the value
of each bone. The third line contain N integers representing the volume of each bone.

Output
One integer per line representing the K-th maximum of the total value (this number will be less than 231).

Sample Input
```3
5 10 2
1 2 3 4 5
5 4 3 2 1
5 10 12
1 2 3 4 5
5 4 3 2 1
5 10 16
1 2 3 4 5
5 4 3 2 1```

Sample Output
```12
2
0```

```#include<stdio.h>
#include<iostream>
#include<string.h>
#include<algorithm>
using namespace std;
#define N 1010
struct nn
{
int usev,w;
}bone[N];
int dp[N],V,K;
int cmp(int a,int b){return a>b;}
int max(int a,int b){return a>b?a:b;}
void zeroonepack(int use,int w)
{
int b,bn,k,i;
for(int v=V;v>=use;v--)
{
for( bn=0,k=0;k<K;k++)
{
b[bn++]=dp[v][k];
b[bn++]=dp[v-use][k]+w;
}
sort(b,b+bn,cmp);
k=0;dp[v]=b;
for(i=1;i<bn&&k<K;i++)
if(dp[v][k]!=b[i])
dp[v][++k]=b[i];
}
}
int main()
{
int t,n;
scanf("%d",&t);
while(t--)
{
scanf("%d%d%d",&n,&V,&K);
for(int i=1;i<=n;i++)
scanf("%d",&bone[i].w);
for(int i=1;i<=n;i++)
scanf("%d",&bone[i].usev);
for(int i=0;i<=V;i++)
for(int j=0;j<=K;j++)
dp[i][j]=0;
for(int i=1;i<=n;i++)
zeroonepack(bone[i].usev,bone[i].w);
printf("%d\n",dp[V][K-1]);
}
}
```