深搜1--城堡问题

Posted 2020-09-23 范仁义

深搜1--城堡问题

一、心得

这个题目的栈实现可以看一看

也是很基础的迷宫问题，也就是一个深搜

二、题目及分析

三、代码及结果

递归

 1 #include <iostream>
 2 #include <stack>
 3 #include <cstring>
 4 using namespace std;
 5 int R,C; //行列数
 6 int rooms[60][60];
 7 int color[60][60]; //房间是否染色过的标记
 8 int maxRoomArea = 0, roomNum = 0;
 9 int roomArea;
10 void Dfs(int i,int k) {
11     if( color[i][k] ) return;
12     ++roomArea;
13     color[i][k] = roomNum;
14     if( (rooms[i][k] & 1) == 0 ) Dfs(i,k-1); //向西走
15     if( (rooms[i][k] & 2) == 0 ) Dfs(i-1,k); //向北
16     if( (rooms[i][k] & 4) == 0 ) Dfs(i,k+1); //向东
17     if( (rooms[i][k] & 8) == 0 ) Dfs(i+1,k); //向南
18 } 
19 
20 int main() {
21     freopen("in.txt","r",stdin); 
22     cin >> R >> C;
23     for( int i = 1;i <= R;++i)
24         for ( int k = 1;k <= C; ++k)
25             cin >> rooms[i][k];
26     memset(color,0,sizeof(color));
27     for( int i = 1;i <= R; ++i)
28         for( int k = 1; k <= C; ++ k) {
29             if( !color[i][k] ) {
30                 ++ roomNum ; roomArea = 0;
31                 Dfs(i,k);
32                 maxRoomArea =max(roomArea,maxRoomArea);
33             }
34         }
35     cout << roomNum << endl;
36     cout << maxRoomArea << endl;
37 }

 

 

栈实现

 1 #include <iostream>
 2 #include <stack>
 3 #include <cstring>
 4 using namespace std;
 5 int R,C; //行列数
 6 int rooms[60][60];
 7 int color[60][60]; //房间是否染色过的标记
 8 int maxRoomArea = 0, roomNum = 0;
 9 int roomArea;
10 struct Room { int r,c; Room(int rr,int cc):r(rr),c(cc) { } };//构造函数用来初始化，
11 void Dfs(int r,int c) { //不用递归，用栈解决，程序其他部分不变
12     stack<Room> stk;
13     stk.push(Room(r,c));
14     while ( !stk.empty() ) {
15         Room rm = stk.top();
16         int i = rm.r; int k = rm.c;
17         if( color[i][k]) stk.pop();
18         else {
19             ++ roomArea;
20             color [i][k] = roomNum;
21             if((rooms[i][k]&1)==0) stk.push(Room(i,k-1));//西
22             if((rooms[i][k]&2)==0) stk.push(Room(i-1,k));//北
23             if((rooms[i][k]&4) == 0) stk.push(Room(i,k+1));//东
24             if((rooms[i][k]&8) == 0) stk.push(Room(i+1,k)); //南
25         }
26     }
27 }
28 
29 int main() {
30     freopen("in.txt","r",stdin); 
31     cin >> R >> C;
32     for( int i = 1;i <= R;++i)
33         for ( int k = 1;k <= C; ++k)
34             cin >> rooms[i][k];
35     memset(color,0,sizeof(color));
36     for( int i = 1;i <= R; ++i)
37         for( int k = 1; k <= C; ++ k) {
38             if( !color[i][k] ) {
39                 ++ roomNum ; roomArea = 0;
40                 Dfs(i,k);
41                 maxRoomArea =max(roomArea,maxRoomArea);
42             }
43         }
44     cout << roomNum << endl;
45     cout << maxRoomArea << endl;
46 }