#include<bits/stdc++.h>
using namespace std;
using ll = long long;

int n,m;
string s;
set<int> apos;
int main(){
  cin >> n >> m >> s;
  for(int i = 0; i < 2 * (n + m); i++){
    if(s[i] == 'C'){
      if(apos.empty()){
        cout << "No";
        return 0;
      }
      int tmp = *begin(apos);
      apos.erase(tmp);
      s[tmp] = 'x';
      s[i] = 'x';
    }
    if(s[i] == 'A') apos.insert(i);
  }
  int cnt = 0;
  for(int i = 0; i < 2 * (n + m); i++){
    if(s[i] == 'W') cnt++;
    if(s[i] == 'A') cnt--;
    if(cnt < 0){
      cout << "No";
      return 0;
    }
  }
  cout << "Yes";
}