const rl = require("readline").createInterface({ input: process.stdin }); var iter = rl[Symbol.asyncIterator](); const readline = async () => (await iter.next()).value; void async function () { // Write your code here const graph = []; const read = await readline(); let ans = 'No' const [n,m] =read.split(' ').map(Number); while(line = await readline()){ let tokens = line.split('') graph.push(tokens); } function dfs(graph){ if(!graph||graph.length === 0)return; const visited = new Set(); const stack = []; function helper(r,c){ if(r<0||c<0||r>n-1||c>m-1)return; if(graph[r][c]!=='.'){ return ; } if(r===n-1&&c===m-1){ ans = 'Yes'; } visited.add([r,c]); graph[r][c] = '#'; //想四个方向搜索道路 helper(r-1,c); helper(r+1,c); helper(r,c-1); helper(r,c+1); } helper(0,0) console.log(ans) } dfs(graph); }()