#include <iostream>
#include <string>

using namespace std;
int par[200010],sz[200010];
void init(int n){
	for(int i=0;i<n;i++) par[i] = i,sz[i] = 1;
}

int find(int x){
	if(par[x]==x) return x;
	return par[x] = find(par[x]);
}

void unite(int x, int y){
	x = find(x); y = find(y);
	if(x==y) return;
	if(sz[x]>sz[y]) swap(x,y);
	par[x] = y; sz[y] += sz[x];
}

bool same(int x, int y){
	return find(x)==find(y);
}

int query(int a,int b){
    cout << a + 1 << " " << b + 1 << endl;
    string t; cin >> t;
    if(t[0]=='B') return 1;
    else return 0;
}

bool used[1010][1010];
int mp[1010][1010];
void dfs(int x,int y,int n){
    if(used[x][y]) return;
    used[x][y] = true;
    int z = query(x,y);
    mp[x][y] = z;
    if(!mp[x][y]) return;
    if(x + 1<n) dfs(x + 1,y,n);
    if(x - 1>=0) dfs(x - 1,y,n);
    if(y + 1<n) dfs(x,y + 1,n);
    if(y - 1>=0) dfs(x,y - 1,n);
}

int main(){
    int i,j,n,m; cin >> n >> m;
    for(i=0;i<n;i++){
        for(j=0;j<n;j++) used[i][j] = false;
    }
    dfs(0,0,n);
    if(used[n - 1][n - 1]) cout << "Yes" << endl;
    else cout << "No" << endl;
}