N皇后问题

#include <IOSTREAM.H>

#include <MATH.H>

#define LENGTH 8

int num=0;

int SuccessInsert(int (*a)[LENGTH],int x,int y)

{

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

    {

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

        {

            if (a[i][j]==1&&(i==x||j==y||abs(x-i)==abs(y-j)))

                return 0;

        }

    }

    a[x][y]=1;

    return 1;

}

void print(int (*a)[LENGTH])

{

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

    {

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

        {

            cout<<a[i][j]<<"  ";

        }

        cout<<endl;

    }

    cout<<++num<<endl;

}

void Back(int (*a)[LENGTH],int x,int count)

{

    if(count==LENGTH)

    {

        print(a);return;

    }

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

    {

        for (int k=0;k<LENGTH;k++)

            a[x][k]=0;

        if (SuccessInsert(a,x,j))

        {

            Back(a,x+1,count+1);

        }

    }

    for (int k=0;k<LENGTH;k++)

            a[x][k]=0;

}

int main()

{

    int a[LENGTH][LENGTH]={0};

    Back(a,0,0);

    cout<<num<<endl;

    print(a);

    return 0;

}