HDU6092 Rikka with Subset-01背包dp-2017多校联盟5 第8题

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Rikka with Subset

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)

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
22 31 1 1 13 31 3 3 1
 

Sample Output
1 21 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
2017 Multi-University Training Contest - Team 5
 



/*题意:一个序列a有n个数,和为m,这个序列能组成2^n个子序列,bi表示这些子序列中和为i的个数现在给你bi,i∈[0,m]求出序列a,a按字典序输出解题思路首先能明确的是b[0]一定等于1,并且b中第一个不为0的i一定有b[i]个。b[i]=i的个数+组合成i的方案数.当确定a中存在i,并且能组合出j-i,那么一定能组合出j,这种途径得到j的方案数就是j-i的方案数*/#include <iostream>#include <cstdio>#include <algorithm>#include <cstring>using namespace std;const int maxn = 1e4 + 10;int dp[maxn];///组合成i的方案数,不包括i本身,(准确的说是在完成第46行循环之前不包括本身。)int b[maxn];int n,m;int main(){    int t;    scanf("%d", &t);    while (t > 0)    {        t--;        memset(dp,0,sizeof(dp));        dp[0] = 1;        scanf("%d%d",&n,&m);        for(int i = 0;i<=m;++i){            scanf("%d",&b[i]);        }        bool f = 0;        for(int i = 1;i<=m;++i){            int cnt = b[i]-dp[i];///b[i]=i的个数+组成i的方案数dp[i]            if(cnt<=0) continue;///不存在i            for(int k = 0;k<cnt;++k){///a里面肯定有cnt个i                if(f) printf(" ");                f=1;                printf("%d",i);                for(int j = m;j>=i;--j){                    dp[j] += dp[j-i];///组成j-i的方案分别加上i就能组成j,加上这种途径获得的方案数                    //dp[j+i] += dp[j];一样的也能过,注意j的范围                }            }        }        puts("");    }    return 0;}

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