uva167 The Sultan's Successors

The Sultan's Successors

Description

The Sultan of Nubia has no children, so she has decided that the country will be split into up to
k separate parts on her death and each part will be inherited by whoever performs best at some test. It is possible for any individual to inherit more than one or indeed all of the portions. To ensure that only highly intelligent people eventually
become her successors, the Sultan has devised an ingenious test. In a large hall filled with the splash of fountains and the delicate scent of incense have been placed
k chessboards. Each chessboard has numbers in the range 1 to 99 written on each square and is supplied with 8 jewelled chess queens. The task facing each potential successor is to place the 8 queens on the chess board in such a way that no queen threatens
another one, and so that the numbers on the squares thus selected sum to a number at least as high as one already chosen by the Sultan. (For those unfamiliar with the rules of chess, this implies that each row and column of the board contains exactly one queen,
and each diagonal contains no more than one.)

Write a program that will read in the number and details of the chessboards and determine the highest scores possible for each board under these conditions. (You know that the Sultan is both a good chess player and a good mathematician and you suspect that
her score is the best attainable.)

Input

Input will consist of k (the number of boards), on a line by itself, followed by
k sets of 64 numbers, each set consisting of eight lines of eight numbers. Each number will be a positive integer less than 100. There will never be more than 20 boards.

Output

Output will consist of k numbers consisting of your k scores, each score on a line by itself and right justified in a field 5 characters wide.

Sample input

1

 1  2  3  4  5  6  7  8

 9 10 11 12 13 14 15 16

17 18 19 20 21 22 23 24

25 26 27 28 29 30 31 32

33 34 35 36 37 38 39 40

41 42 43 44 45 46 47 48

48 50 51 52 53 54 55 56

57 58 59 60 61 62 63 64

Sample output

Accepted 0ms（评测来源：Virtual Judge）

编写编译环境：ubuntu（linux），emacs

题目大意：苏丹努比亚（似乎在哪里听过，一千零一夜？）年事已高，向划分疆域给继承者。选择继承者需Ta足够机智。于是，她用经典的八皇后问题，外加棋盘上多了系数，每取一个皇后累加皇后坐标上的数字，求最大数字。

思路：完全行行枚举，暴力判断。。。

#include<cstdio>

#include<cstring>

#include<iostream>

using namespace std;

int boa[8][8],qnn[8][2],ans;

bool col[8];

void Init()

{

  ans=0;

  memset(col,0,sizeof(col));

  for(int i=0;i<8;i++)

    for(int j=0;j<8;j++)

      scanf("%d",&boa[i][j]);

}

bool jud(int x,int y)

{

  for(int i=0;i<x;i++)

    if((qnn[i][0]==qnn[i][1]&&x==y)||(x+y==qnn[i][0]+qnn[i][1])||(x-y==qnn[i][0]-qnn[i][1]))

      return false;

  return true;

}

void dfs(int cur,int sum)

{

  if(cur==8){

    ans=max(ans,sum);

    return;

  }

  for(int j=0;j<8;j++)

    if((!col[j])&&jud(cur,j)){

      col[j]=1;

      qnn[cur][0]=cur;

      qnn[cur][1]=j;

      dfs(cur+1,sum+boa[cur][j]);//cur means columns,every column has a queen;

      col[j]=0;

    }

}

int main()

{

  int T;

  scanf("%d",&T);

  while(T--){

    Init();

    dfs(0,0);

    printf("%5d\n",ans);

  }

  return 0;

}