数据结构－－－八皇后问题

算法思想：利用行号固定，列号全排列解决；这样没有i ＝＝ j 和board［i] ＝＝ board［j］的冲突；

只要检测(j-i) == (size_t)abs(board[i]-board[j])就说明冲突！

1 #include <cmath>

2 #include <iostream>

3 #include <vector>

4 #include <algorithm>

5

6 using namespace std;

7 const int MAX = 8;

8

9 vector<int> board(MAX);

10

11 void show_result()

12 {

13 for(size_t i = 0; i < board.size(); i++)

14 cout<<"("<<i<<","<<board[i]<<")";

15 cout<<endl;

16 }

17

18 int check_cross()

19 {

20 for(size_t i = 0; i < board.size()-1; i++)

21 {

22 for(size_t j = i+1; j < board.size(); j++)

23 {

24 if((j-i) == (size_t)abs(board[i]-board[j]))

25 return 1;

26 }

27 }

28 return 0;

29 }

30

31 void put_chess()

32 {

33 while(next_permutation(board.begin(), board.end()))

34 {

35 if(!check_cross())

36 {

37 show_result();

38 }

39 }

40 }

41

42 int main()

43 {

44 for(size_t i =0; i < board.size(); i++)

45 board[i] = i;

46 put_chess();

47 return 0;

48 }