1.从外围搜索O，深度搜索出现了
| Line 35: java.lang.StackOverflowError | |
| Last executed input: | ["OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO |
1 public class Solution { 2 public void solve(char[][] board) { 3 if(board.length==0) return; 4 int len1=board.length; 5 int len2=board[0].length; 6 for(int i=0;i<len1;i++) 7 { 8 if(board[i][0]=='O') dfs(board,i,0); 9 if(board[i][len2-1]=='O') dfs(board,i,len2-1); 10 11 } 12 for(int i=0;i<len2;i++) 13 { 14 15 if(board[0][i]=='O')dfs(board,0,i); 16 if(board[len1-1][i]=='O')dfs(board,len1-1,i); 17 } 18 for(int i=0;i<len1;i++) 19 { 20 for(int j=0;j<len2;j++) 21 { 22 if(board[i][j]=='h') board[i][j]='O'; 23 else board[i][j]='X'; 24 } 25 } 26 27 28 } 29 public void dfs(char b[][],int i,int j) 30 { 31 if(i<0||i>b.length-1||j<0||j>b[0].length-1) return; 32 if(b[i][j]!='O') return; 33 34 if(b[i][j]=='O') b[i][j]='h'; 35 dfs(b,i+1,j);//up 36 dfs(b,i-1,j);//down 37 dfs(b,i,j+1);//left 38 dfs(b,i,j-1);//right; 39 40 41 } 42 }
2.广度搜索一定可以了。抽空在写，（可惜不行，我太水了超时代码）
class node { int x; int y; char c; node(int x1,int y1,char c1) { x=x1; y=y1; c=c1; } } public class Solution { public void solve(char[][] board) { if(board.length==0) return; int len1=board.length; int len2=board[0].length; for(int i=0;i<len1;i++) { if(board[i][0]=='O') bfs(board,i,0); if(board[i][len2-1]=='O') bfs(board,i,len2-1); } for(int i=0;i<len2;i++) { if(board[0][i]=='O')bfs(board,0,i); if(board[len1-1][i]=='O')bfs(board,len1-1,i); } for(int i=0;i<len1;i++) { for(int j=0;j<len2;j++) { if(board[i][j]=='h') board[i][j]='O'; else board[i][j]='X'; } } } public boolean is(int i,int j,int len1,int len2,char c[][]) { if(i>=0&&i<len1&&j>=0&&j<len2&&c[i][j]=='O') return true; return false; } //put the o to h public void bfs(char b[][],int i,int j) { int len1=b.length; int len2=b[0].length; Queue<node> queue=new LinkedList<node>(); queue.offer(new node(i,j,b[i][j])); while(!queue.isEmpty()) { node n1=queue.poll(); b[n1.x][n1.y]='h'; if(is(n1.x,n1.y+1,len1,len2,b)) { queue.offer(new node(n1.x,n1.y+1,b[n1.x][n1.y+1])); } if(is(n1.x,n1.y-1,len1,len2,b)) { queue.offer(new node(n1.x,n1.y-1,b[n1.x][n1.y-1])); } if(is(n1.x+1,n1.y,len1,len2,b)) { queue.offer(new node(n1.x+1,n1.y,b[n1.x+1][n1.y])); } if(is(n1.x-1,n1.y,len1,len2,b)) { queue.offer(new node(n1.x-1,n1.y,b[n1.x-1][n1.y])); } } } }