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 }
