zoukankan      html  css  js  c++  java
  • 2017杭电多校第五场Rikka with Subset



    Rikka with Subset

    Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
    Total Submission(s): 1440    Accepted Submission(s): 721


    Problem Description
    As we know, Rikka is poor at math. Yuta is worrying about this situation, so he gives Rikka some math tasks to practice. There is one of them:

    Yuta has n positive A1An and their sum is m. Then for each subset S of A, Yuta calculates the sum of S

    Now, Yuta has got 2n numbers between [0,m]. For each i[0,m], he counts the number of is he got as Bi.

    Yuta shows Rikka the array Bi and he wants Rikka to restore A1An.

    It is too difficult for Rikka. Can you help her?  
     

    Input
    The first line contains a number t(1t70), the number of the testcases. 

    For each testcase, the first line contains two numbers n,m(1n50,1m104).

    The second line contains m+1 numbers B0Bm(0Bi2n).
     

    Output
    For each testcase, print a single line with n numbers A1An.

    It is guaranteed that there exists at least one solution. And if there are different solutions, print the lexicographic minimum one.
     

    Sample Input
    2 2 3 1 1 1 1 3 3 1 3 3 1
     

    Sample Output
    1 2 1 1 1
    Hint
    In the first sample, $A$ is $[1,2]$. $A$ has four subsets $[],[1],[2],[1,2]$ and the sums of each subset are $0,1,2,3$. So $B=[1,1,1,1]$
     

    Source
     

    Recommend
    liuyiding   |   We have carefully selected several similar problems for you:  6095 6094 6093 6092 6091 
     

    Statistic | Submit | Discuss | Note


    思路:动态规划+思维
    因为已知了集合B要求集合A的序列,显然空集与全集的数量都为1,所以B0和Bm都为1
    集合A中1的数量就等于B1,那么B2便可以由B1推出(排列组合的思想),B3可有B2推出,以此类推,采用01背包为题解决
    #include <iostream>
    #include<algorithm>
    #include<string.h>
    #include<stdint.h>
    using namespace std;
    const int maxn=10005;
    
    int a[maxn],b[maxn],c[maxn],dp[maxn];
    //dp[i]表示:加和为i的子集个数
    
    int main()
    {
        int t;
        scanf("%d",&t);
        int n,m;
        while(t--)
        {
            scanf("%d%d",&n,&m);
            memset(a,0,sizeof(a));
            memset(b,0,sizeof(b));
            memset(c,0,sizeof(c));
            memset(dp,0,sizeof(dp));
    
            dp[0]=1;
            for(int i=0;i<=m;i++)
            {
              scanf("%d",&b[i]);
            }
            int p=0,sum=0;
            for(int i=1;i<=m;i++)
            {
                c[i]=b[i]-dp[i];//A序列中值为i的个数
                for(int j=0;j<c[i];j++)
                {
                    a[p++]=i;//对A序列赋值
                    for(int k=m;k>=i;k--)
                    {//处理成01背包问题
                        dp[k]+=dp[k-i];//和为k的子集个数相加去更新B序列
    
                    }
                }
    
            }
            for(int i=0;i<p-1;i++)
            {
                printf("%d ",a[i]);
    
            }
            printf("%d
    ",a[p-1]);
        }
        return 0;
    }
    


  • 相关阅读:
    Activity表单传值问题
    求助~!线程里不能MediaRecorder.start()
    获取浏览器的宽高:
    WebStorm快捷键收集
    CSS中强大的EM
    常用global.css
    常用base.css
    自适应网页设计的方法(手机端良好的访问体验)
    还需要学习的十二种CSS选择器
    js 根据屏幕大小调用不同的css文件
  • 原文地址:https://www.cnblogs.com/bryce1010/p/9387442.html
Copyright © 2011-2022 走看看