#include <bits/stdc++.h> 
using namespace std;
using ll =long long;
#define all(v) v.begin(),v.end()
 #define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)

int main() {
    ll N,M;cin>>N>>M;
    string S;
    cin>>S;
    
    queue<ll> Q;
    vector<bool> note(2*(N+M));

    for(ll i=0;i<2*(N+M);i++) {
      if(S[i]=='A') Q.push(i);
      else if(S[i]=='C') {
        if(Q.empty()) {
          cout<<"No"<<endl;
          return 0;
        }
        else {
          auto p=Q.front();
          Q.pop();
          note[p]=true;
        }
      }
    }

queue<ll> T;

    for(ll i=2*(N+M)-1;i>=0;i--) {
      if(note[i]||S[i]=='C') continue;
     if(S[i]=='A') T.push(i);
     else {
      if(T.empty()) {
        cout<<"No"<<endl;
        return 0;
      }
      else {
        T.pop();
      }
     }
    }

    cout<<"Yes"<<endl;
}