BFS in View

  1 //BFS
  2 #include<list>
  3 #include<queue>
  4 #include<time.h>
  5 #include<algorithm>
  6 #include<graphics.h>
  7 using namespace std;
  8 /*------------全局变量----------------*/
  9 int   Wndl = 500;              //窗口大小
 10 int  Count = 25;               //节点数量25*25
 11 int  Width = Wndl  / Count;    //绘图的正方形长度
 12 int Radius = Width / 2;        //正方形中点到边的距离
 13 struct Pot {
 14     int x0, y0; //正方形中点
 15     int flag;   //1表示障碍，初始化零表示未知
 16     Pot(int x, int y, int f) :x0(x), y0(y), flag(f) {}
 17     friend bool operator==(const Pot &arg0, const Pot &arg1) {
 18         if (arg0.x0 == arg1.x0&&arg0.y0 == arg1.y0)
 19             return true;
 20         return false;
 21     }
 22     //为获得队列起始，队列目标的方法
 23     Pot ForQue(int f) {
 24         flag = f;
 25         return *this;
 26     }
 27 };
 28 /*----------函数的向前声明--------------*/
 29           list<Pot> CreatPots();
 30                void CreatMap(list<Pot>&);
 31 list<Pot>::iterator GetIter(list<Pot>&, int);
 32 list<Pot>::iterator SearchPot(list<Pot>&, Pot, int);
 33 //主函数
 34 int main() {
 35     //获得所有节点
 36     list<Pot> Potlist = move(CreatPots());
 37     //地图的产生
 38     HWND hwnd = initgraph(Wndl, Wndl);
 39     CreatMap(Potlist);
 40     //起始点、终点的随机产生，并特殊标记
 41     srand((unsigned int)time(NULL));
 42     int Max = Count * Count;
 43     int BnCt = rand() % Max;
 44     int EnCt = rand() % Max;
 45     Pot  Begin_Pot = GetIter(Potlist, BnCt)->ForQue(1);
 46     Pot Target_Pot = GetIter(Potlist, EnCt)->ForQue(0);
 47     setfillcolor(RED);
 48     fillrectangle(Begin_Pot.x0 - Radius, Begin_Pot.y0 - Radius, Begin_Pot.x0 + Radius, Begin_Pot.y0 + Radius);
 49     fillrectangle(Target_Pot.x0 - Radius, Target_Pot.y0 - Radius, Target_Pot.x0 + Radius, Target_Pot.y0 + Radius);
 50     //广度优先搜索
 51     setlinecolor(WHITE);
 52     queue<Pot> Potque;
 53     Potque.push(Begin_Pot);
 54     while (!Potque.empty()) {
 55         Pot ThePot = Potque.front();
 56         Potque.pop();
 57         for (int i = 0; i < 4; i++) {
 58             auto Iter = SearchPot(Potlist, ThePot, i);
 59             if (Iter == Potlist.end())
 60                 continue;
 61             Sleep(200);
 62             line(ThePot.x0, ThePot.y0, Iter->x0, Iter->y0);
 63             Potque.push(*Iter);
 64             if (*Iter == Target_Pot)
 65                 goto OK;
 66             Potlist.erase(Iter);
 67         }
 68     }
 69     //搜索结束，离开界面
 70     MessageBox(hwnd, L"Search default", L"BFS", MB_OK);
 71     if (0) {
 72     OK:
 73         MessageBox(hwnd, L"OK", L"BFS", MB_OK);
 74     }
 75     closegraph();
 76     return 0;
 77 }
 78 //包含所有节点的容器
 79 list<Pot> CreatPots() {
 80     srand((unsigned int)time(NULL));
 81     list<Pot> Potlist;
 82     for (int i = 0; i < Count; i++)
 83         for (int j = 0; j < Count; j++)
 84             Potlist.push_back(
 85                 { i*Width + Radius,j*Width + Radius,(int)(rand() % 2 && rand() % 2) });
 86     return Potlist;
 87 }
 88 //界面的初始化
 89 void CreatMap(list<Pot>&Potlist) {
 90     setlinecolor(GREEN);
 91     for (int i = 1; i < Count; i++) {
 92         int pos = i * Width;
 93         line(0, pos, Wndl, pos);
 94         line(pos, 0, pos, Wndl);
 95     }
 96     setfillcolor(LIGHTGRAY);
 97     int R = Radius;
 98     for_each(Potlist.begin(), Potlist.end(),
 99         [R](Pot it) {
100         if (it.flag == 1)
101             fillrectangle(it.x0 - R + 1, it.y0 - R + 1, it.x0 + R - 1, it.y0 + R - 1); });
102 }
103 //为获得起点、终点
104 list<Pot>::iterator GetIter(list<Pot> &Potlist, int times) {
105     auto Iter = Potlist.begin();
106     for (int i = 0; i < times; i++)
107         Iter++;
108     return Iter;
109 }
110 //寻找要入队列的节点
111 list<Pot>::iterator SearchPot(list<Pot> &pots, Pot arg, int flag) {
112     switch (flag) {
113     case 0:arg.x0 -= Width; break;
114     case 1:arg.x0 += Width; break;
115     case 2:arg.y0 -= Width; break;
116     case 3:arg.y0 += Width; break;
117     default:return pots.end();
118     }
119     list<Pot>::iterator it =
120         find_if(pots.begin(), pots.end(), [arg](Pot it) {
121             if (it.flag == 1) return false;
122             if (it == arg) return true;
123             return false; });
124     return it;
125 }