#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>
#include <complex>
#include <cassert>

using namespace std;
using ll = long long;

int main(){

    int N, M, w=0, a, c=0;
    string S;
    cin >> N >> M >> S;
    a = N+M;
 
    for (int i=0; i<(N+M)*2; i++){
        if (S[i] == 'W') w++;
        else if (S[i] == 'A') a--;
        if (w > a && w != N){
            cout << "No" << endl;
            return 0;
        }
    }
    a = N+M;
    for (int i=(N+M)*2-1; i>=0; i--){
        if (S[i] == 'C') c++;
        else if (S[i] == 'A') a--;
        if (c > a && c != M){
            cout << "No" << endl;
            return 0;
        }
    }

    cout << "Yes" << endl;

    return 0;
}