四阶幻方的穷举求解.

速度太慢了,有时间研究构造四阶幻方的构造法…..

#include "iostream"
#include "algorithm"
#include "queue"
#include "vector"
#include "list"
using namespace std;
bool isused[17] = { false };
int board[17];
queue<int>x;

#define M 34
void print(int count)
{
    cout << "case :" << count << endl;
    for (size_t beg = 1; beg != 17; beg+=4)
    {
        cout << board[beg] << " \t" << board[beg + 1] << "\t "
            << board[beg + 2] << " \t" << board[beg + 3]<<endl;
    }
    cout<< "====================================" << endl;

}
bool check()
{
    if (board[13] + board[14] + board[15] + board[16] != M)
        return false;
    return board[1] + board[6] + board[11] + board[16] == M&& 
        board[4] + board[7] + board[10] + board[13] == M ? true : false;
}
void func(int n)
{
    static int index = 0;
    if (n == 17)
    {
        if (check())//符合要求
            print(++index);

        return;
    }

    if(n<=12)
    {
        int count = x.size();
        while (--count!=-1)//使用队列里面现有的元素
        {
            auto m = x.front();
            x.pop();
            board[n] = m;
            isused[m] = true;
            do
            {
                if (!(n % 4) && board[n] + board[n - 1] + board[n - 2] + board[n - 3] != M)
                    break;
                if (n ==11 && board[n] + board[n - 1] + board[n - 4] + board[n - 5] != M)
                    break;
              func(n + 1);
            } while (0);
            isused[m] = false;
            x.push(m);
        }
    }
    else
    {
        int m = M - board[n - 4] - board[n - 8] - board[n - 12];
        if (m > 0 && m < 17 && !isused[m])
        {
            board[n] = m;
            isused[m] = true;
            func(n + 1);
            isused[m] = false;
        }
    }
}
int main()
{
    for (size_t i = 1; i != 17; ++i)
        x.push(i);
    func(1);

    return 0;
}