八皇后问题

#include <bits/stdc++.h>
#define _for(i,a,b) for(int i = (a);i < (b);i ++)
using namespace std;

const int n = 8;
vector<vector<vector<int>>> rnt;
vector<vector<int>> C (n,vector<int> (n,0));

int vis[3][39];

void search(int cur)
{
    if(cur==n)
        rnt.push_back(C);
    else
        _for(i,0,n)
        {
            if(!vis[0][i] && !vis[1][cur+i] && !vis[2][i-cur+n])
            {
                C[cur][i] = vis[0][i] = vis[1][cur+i] = vis[2][i-cur+n] = 1;
                search(cur+1);
                C[cur][i] = vis[0][i] = vis[1][cur+i] = vis[2][i-cur+n] = 0;
            }
        }
} 

void print()
{
    int kase = 1;
    _for(i,0,rnt.size())
    {
        cout << "Case:" << kase++ << endl;
        _for(j,0,rnt[i].size())
        {
            _for(k,0,rnt[i][j].size())
            {
                if(rnt[i][j][k])
                    cout << 'Q' << " ";
                else
                    cout << '.' << " ";
            }
            cout << endl;
        }
        cout << endl << endl;
    }
}

int main()
{
 //    freopen("output.txt","w",stdout);
    memset(vis,0,sizeof(vis));
    search(0);
    print();
    return 0;
}

vis[0]判列，vis[1]判主对角线，vis[2]判副对角线