代码实现class Solution { int dx[4] {1,-1,0,0}; int dy[4] {0,0,-1,1}; typedef pairint,int PII; int n,m; public: int numEnclaves(vectorvectorint grid) { n grid.size(); m grid[0].size(); vectorvectorbool vis(grid.size(),vectorbool(grid[0].size(),false));//标记遍历过的数组 for(int i 0; i m; i)//处理边界1 { Bfs(0,i,grid,vis); Bfs(n - 1,i,grid,vis); } for(int i 0; i n; i)//处理边界1 { Bfs(i,0,grid,vis); Bfs(i,m - 1,grid,vis); } int ret 0; for(int i 0; i n; i)//此时中间的 1 就是陆地 { for(int j 0; j m; j) { if(vis[i][j] false grid[i][j]) { ret Bfs(i,j,grid,vis); } } } return ret; } int Bfs(int i,int j,vectorvectorint grid,vectorvectorbool vis)//BFS 算法 { if(grid[i][j] ! 1 || vis[i][j] ! false) return 0; queuePII que; que.push({i,j}); vis[i][j] true; int count 1; while(que.size()) { auto [x,y] que.front(); que.pop(); for(int v 0; v 4; v) { int a x dx[v]; int b y dy[v]; if(a 0 a n b 0 b m vis[a][b] false grid[a][b]