#include <iostream>
#include <algorithm>
#include <vector>
#include <deque>
#include <queue>
#include <set>
#include <map>
#include <limits>
#include <cmath>
#include <iomanip>
#include <functional>
#include <random>
#include <set>
using namespace std;
using ll = long long;

int main()
{
    // 整数の入力
    ll N,M;
    cin >> N >> M;
    string S;
    cin >> S;
    deque<ll> W;
    deque<ll> A;
    deque<ll> C;
    for(int i = 0;i < S.size();i++){
        if (S[i] == 'W'){
            W.push_back(i);
        }else if (S[i] == 'A'){
            A.push_back(i);
        }else{
            C.push_back(i);
        }
    }
    while(!W.empty()){
        if (W.back() < A.back()){
            W.pop_back();
            A.pop_back();
        }else{
            cout << "No" << endl;
            return 0;
        }
    }
    while(!C.empty()){
        if (A.front() < C.front()){
            C.pop_front();
            A.pop_front();
        }else{
            cout << "No" << endl;
            return 0;
        }
    }
    cout << "Yes" << endl;
    return 0;
}