八皇后问题

 1 #include <bits/stdc++.h>
 2 #define _for(i,a,b) for(int i = (a);i < (b);i ++)
 3 using namespace std;
 4 
 5 const int n = 8;
 6 vector<vector<vector<int>>> rnt;
 7 vector<vector<int>> C (n,vector<int> (n,0));
 8 
 9 int vis[3][39];
10 
11 void search(int cur)
12 {
13     if(cur==n)
14         rnt.push_back(C);
15     else
16         _for(i,0,n)
17         {
18             if(!vis[0][i] && !vis[1][cur+i] && !vis[2][i-cur+n])
19             {
20                 C[cur][i] = vis[0][i] = vis[1][cur+i] = vis[2][i-cur+n] = 1;
21                 search(cur+1);
22                 C[cur][i] = vis[0][i] = vis[1][cur+i] = vis[2][i-cur+n] = 0;
23             }
24         }
25 } 
26 
27 void print()
28 {
29     int kase = 1;
30     _for(i,0,rnt.size())
31     {
32         cout << "Case:" << kase++ << endl;
33         _for(j,0,rnt[i].size())
34         {
35             _for(k,0,rnt[i][j].size())
36             {
37                 if(rnt[i][j][k])
38                     cout << 'Q' << " ";
39                 else
40                     cout << '.' << " ";
41             }
42             cout << endl;
43         }
44         cout << endl << endl;
45     }
46 }
47 
48 int main()
49 {
50  //    freopen("output.txt","w",stdout);
51     memset(vis,0,sizeof(vis));
52     search(0);
53     print();
54     return 0;
55 }


vis[0]判列，vis[1]判主对角线，vis[2]判副对角线