#pragma GCC target("avx") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include<bits/stdc++.h> int N,M; char s[7]; bool vis[500][500]; inline bool q(int i,int j) noexcept{ vis[i][j]=true; printf("%d %d\n",i+1,j+1); scanf("%s",s); return s[0]=='B'; } void dfs(int i,int j){ if(i==N-1&&j==N-1){ puts("Yes"); exit(0); } if(i+1<N&&!vis[i+1][j]&&q(i+1,j))dfs(i+1,j); if(j+1<N&&!vis[i][j+1]&&q(i,j+1))dfs(i,j+1); if(i&&!vis[i-1][j]&&q(i-1,j))dfs(i-1,j); if(j&&!vis[i][j-1]&&q(i,j-1))dfs(i,j-1); } int main(){ scanf("%d %d",&N,&M); vis[0][0]=true; dfs(0,0); puts("No"); }