題意：給你n個房間,有許多燈的控制開關,i房間燈的開關在j房間,未開燈的房間不能進,i房間和j房間之間如果沒有門,也不能從i進入到j,開始房間是1，並且燈是開著的,問你是否能夠走到最後一個房間n,並且此時其他房間的燈都是關著的.如果存在多個解,輸出操作步數最小的操作序列.

範圍：n<=10,

解題思路:設狀態為,當前的房間編號+當前其他房間燈的狀態.所以總的狀態為N*2^N,最大值10*1024，裸列舉.

注意，這道題目每次列舉都必須從房間編碼1-N,要不然會wa，而且,PE也wa.使用了位標誌房間燈的狀態.

#include <iostream>
#include
 
<map>
#include<memory.h>
#include<stdio.h>
#include<string>
#include<queue>
#include<vector>
using namespace std;
const int  MAXN = 11;

class Node
{
public:
    vector<string>step;
    int cur;
    int curStepNum;
    int lights;
    Node()
    {
        
 
//step.reserve(65535);
    }
    bool operator <(const Node& node) const
    {
        return curStepNum > node.curStepNum;
    };
};
int conn[MAXN][MAXN];
int contro[MAXN][MAXN];
int r, d, s;
int states[10][1025];
priority_queue<Node>q;
int perLights[10] = {
    1 << 0,1
 
 << 1,1 << 2 ,1 << 3 ,1 << 4 ,1 << 5 ,
    1 << 6,1 << 7,1 << 8 ,1 << 9 };



void read()
{
    int ss, ee;
    for (int i = 0;i < d;i++)
    {
        cin >> ss >> ee;
        //start with 0
        conn[ss - 1][ee - 1] = 1;
        conn[ee - 1][ss - 1] = 1;
    }
    for (int i = 0;i < s;i++)
    {
        cin >> ss >> ee;
        contro[ss - 1][ee - 1] = 1;
    }
}
Node bfs()
{
    Node node;
    node.cur = 0;
    node.curStepNum = 0;
    node.lights = 1;
    q.push(node);
    //init node 只有0房間是亮的
    states[0][1] = 1;
    while (q.empty() == false)
    {
        node = q.top();
        q.pop();
        int curIndex = node.cur;
        //cur lights state
        int curLights = node.lights;
        int curStepNum = node.curStepNum;
        //判斷是不是終點
        if ((curIndex == r - 1) && curLights == perLights[r - 1])
        {
            return node;
        }
    
        //列舉燈的狀態
        for (int i = 0;i < 10; i++)
        {
            if (contro[curIndex][i] == 0)
                continue;
            if (i == curIndex)
                continue;
            //控制的燈
            int nextControLightIndex = i;
            string desc = "";
            int nextLight = 0;
            if ((curLights & perLights[nextControLightIndex]) == perLights[nextControLightIndex])
            {
                //關閉next房間的燈
                nextLight = (curLights ^ perLights[nextControLightIndex]);
                if (states[curIndex][nextLight] == 1)
                    //repeat
                    continue;
                desc = "- Switch off light in room " + std::to_string(nextControLightIndex + 1);
                desc += ".";
            }
            else
            {
                //開啟next房間的燈
                nextLight = curLights | perLights[nextControLightIndex];
                if (states[curIndex][nextLight] == 1)
                    //repeat
                    continue;
                desc = "- Switch on light in room " + std::to_string(nextControLightIndex + 1);
                desc += ".";
            }
            Node newNode;
            newNode.curStepNum = curStepNum + 1;
            newNode.cur = curIndex;
            newNode.lights = nextLight;
            newNode.step = node.step;
            newNode.step.push_back(desc);
            //push to queue
            q.push(newNode);
            states[curIndex][nextLight] = 1;
        }
        //end curIndex enum lights state
        //start door
        for (int i = 0;i < 10;i++)
        {
            if (curIndex == i)
                continue;
            if (conn[curIndex][i] == 0)
                continue;
            int nextDoor = i;
            if ((perLights[nextDoor] & curLights) == 0)
                //燈是滅的,不能進
                continue;
            if (states[nextDoor][curLights] == 1)
                //已經看到過,不能進
                continue;
            //燈是開著的,能進
            Node newNode;
            newNode.cur = nextDoor;
            newNode.curStepNum = curStepNum + 1;
            newNode.lights = curLights;
            newNode.step = node.step;
            string desc = "- Move to room " + std::to_string(nextDoor + 1);
            desc += ".";
            newNode.step.push_back(desc);
            states[nextDoor][curLights] = 1;
            q.push(newNode);
        }
    }
    node.cur = -1;
    return node;
}
int main()
{
    int t = 0;
    while (cin >> r >> d >> s)
    {
        if (r == d && d == s && r == 0)
            break;
        memset(conn, 0, sizeof(conn));
        memset(contro, 0, sizeof(conn));
        memset(states, 0, sizeof(states));
        while (q.empty() == false)
            q.pop();
        read();
        
        cout << "Villa #";
        cout << t + 1 << endl;
        if (r == 1)
        {
            cout << "The problem can be solved in " << 0 << " steps:" << endl;

        }
        else
        {
            Node node = bfs();
            //cout << "test" << endl;
            if (node.cur == -1)
            {
                cout << "The problem cannot be solved." << endl;
            }
            else
            {
                cout << "The problem can be solved in " << node.curStepNum << " steps:" << endl;
                vector<string> b = node.step;
                for (int i = 0;i <= b.size() - 1;i++)
                    cout << b[i] << endl;;
            }
        }
        t++;
        cout << endl;
    }


}