需要注意的是，比如如下代码：
Node tmp5 = new Node();
tmp5.col = node.col;
tmp5.row = node.row;
stackk.Push(tmp5);
为什么不是直接 stackk.Push(node);不是更方便吗
由于本人知识浅薄，还没悟出其中缘由，脑海里依稀认为 若是直接“=”赋值便是赋值而不是引用，node的变化应该不会改变stackk.Peek()的值才对，如果要修改应该要加入ref类似的标记，但是事实却是如果 node=stackk.Peek();修改 node的值之后，stackk.Peek()值也会发生改变，所以需要上面代码这么写才不会改变栈里面原来的值
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace EightQueenNotRecursive
{
class Program
{
int[] a = new int[8];
int solution = 1;
public class Node
{
public int row;
public int col;
}
public bool isOK(Node node)
{
for (int i = 0; i <node.row; i++)
{
if (a[i]==node.col|| node.row - i == Math.Abs(a[i]-node.col))
{
return false;
}
}
return true;
}
public void Print()
{
Console.WriteLine("第{0}种解法:", solution++);
for (int i = 0; i < 8; i++)
{
for (int j = 0; j < 8; j++)
{
if (a[i]==j)
{
Console.Write("Q");
}else
{
Console.Write("#");
}
}
Console.WriteLine();
}
Console.WriteLine("--------");
}
void DSF()
{
Node node=new Node();
Stack stackk = new Stack();
node.row = 0;
node.col = 0;
stackk.Push(node);
while (stackk.Count !=0)
{
Node tmp = new Node();
tmp= (Node)stackk.Peek();
node.row = tmp.row;
node.col = tmp.col;
while (!isOK(node) && node.col < 8)
{
node.col++;
}
if (node.col < 8)
{
//forward
if (node.row <7)
{
//把ok的节点放到当前层
a[node.row] = node.col;
stackk.Pop();
Node tmp4 = new Node();
tmp4.col = node.col;
tmp4.row = node.row;
stackk.Push(tmp4);
//进入下一层的第一个节点
node.row++;
node.col = 0;
Node tmp3 = new Node();
tmp3.col = node.col;
tmp3.row = node.row;
stackk.Push(tmp3);
}
else
{
a[node.row] = node.col;
//done
Print();
node.col++;
stackk.Pop();
Node tmp6 = new Node();
tmp6.col = node.col;
tmp6.row = node.row;
stackk.Push(tmp6);
}
}
else
{
stackk.Pop();
if (stackk.Count == 0)
{
return;
}
Node tmp1 = new Node();
tmp1 = (Node)stackk.Peek();
node.row = tmp1.row;
node.col = tmp1.col;
node.col++;
stackk.Pop();
Node tmp5 = new Node();
tmp5.col = node.col;
tmp5.row = node.row;
stackk.Push(tmp5);
//back
}
}
}
static void Main(string[] args)
{
Program p = new Program();
foreach(int i in p.a)
{
p.a[i] = 0;
}
p.DSF();
Console.ReadKey();
}
}
}
