首页 > 代码库 > HDU3535AreYouBusy[混合背包 分组背包]

HDU3535AreYouBusy[混合背包 分组背包]

2024-08-14 12:03:15   225人阅读

AreYouBusy

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 3985    Accepted Submission(s): 1580


Problem Description
Happy New Term!
As having become a junior, xiaoA recognizes that there is not much time for her to AC problems, because there are some other things for her to do, which makes her nearly mad.
What‘s more, her boss tells her that for some sets of duties, she must choose at least one job to do, but for some sets of things, she can only choose at most one to do, which is meaningless to the boss. And for others, she can do of her will. We just define the things that she can choose as "jobs". A job takes time , and gives xiaoA some points of happiness (which means that she is always willing to do the jobs).So can you choose the best sets of them to give her the maximum points of happiness and also to be a good junior(which means that she should follow the boss‘s advice)?
 

 

Input
There are several test cases, each test case begins with two integers n and T (0<=n,T<=100) , n sets of jobs for you to choose and T minutes for her to do them. Follows are n sets of description, each of which starts with two integers m and s (0<m<=100), there are m jobs in this set , and the set type is s, (0 stands for the sets that should choose at least 1 job to do, 1 for the sets that should choose at most 1 , and 2 for the one you can choose freely).then m pairs of integers ci,gi follows (0<=ci,gi<=100), means the ith job cost ci minutes to finish and gi points of happiness can be gained by finishing it. One job can be done only once.
 

 

Output
One line for each test case contains the maximum points of happiness we can choose from all jobs .if she can’t finish what her boss want, just output -1 .
 

 

Sample Input
3 32 12 53 82 01 02 13 24 32 11 13 42 12 53 82 01 12 83 24 42 11 11 11 02 15 32 01 02 12 02 21 12 03 22 12 11 52 83 23 84 95 10
 

 

Sample Output
513-1-1
 

 

Author
hphp
 

 

Source
2010 ACM-ICPC Multi-University Training Contest（10）——Host by HEU 
题意：n组，每组m个物品，有三种类型：至少选一个，至多选一个，随便选
 

d[i][j]表示前i组体积j的最大值
至少选一个：d[i][j]=-INF，保证了至少一个
　　　　　　d[i][j]=max(d[i][j],max(d[i][j-v[x]]+w[x],d[i-1][j-v[x]]+w[x])) 因为可以选多个 【WARN：不能分成两次max，因为保证至少选一个-INF】
至多选一个：d[i][j]=d[i-1][j]，d[i][j]=max(d[i][j],d[i-1][j-v[x]]+w[x]) 可以不选，普通分组背包
随便：d[i][j]=d[i-1][j]，d[i][j]=max(d[i][j],d[i][j-v[x]]+w[x]); 可以不选，也可以选多个
#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<cmath>using namespace std;const int N=105,INF=1e9;int read(){    char c=getchar();int x=0,f=1;    while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1; c=getchar();}    while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘; c=getchar();}    return x*f;}int n,t,m,s,v[N],w[N];int d[N][N];int main(){    while(cin>>n>>t){        memset(d,0,sizeof(d));        for(int i=1;i<=n;i++){            m=read();s=read();                for(int x=1;x<=m;x++){                v[x]=read();w[x]=read();                    }            if(s==0){                for(int j=0;j<=t;j++) d[i][j]=-INF;                for(int x=1;x<=m;x++)                    for(int j=t;j>=v[x];j--)                        d[i][j]=max(d[i][j],max(d[i][j-v[x]]+w[x],d[i-1][j-v[x]]+w[x]));            }            else if(s==1){                for(int j=0;j<=t;j++) d[i][j]=d[i-1][j];                for(int x=1;x<=m;x++)                    for(int j=t;j>=v[x];j--)                        d[i][j]=max(d[i][j],d[i-1][j-v[x]]+w[x]);            }            else if(s==2){                for(int j=0;j<=t;j++) d[i][j]=d[i-1][j];                for(int x=1;x<=m;x++)                    for(int j=t;j>=v[x];j--)                        d[i][j]=max(d[i][j],d[i][j-v[x]]+w[x]);            }        }        printf("%d\n",max(d[n][t],-1));        }}

 

 

HDU3535AreYouBusy[混合背包 分组背包]


联系
我们