#include<bits/stdc++.h>

using namespace std;
using ll = long long;

int main(){
    int n, m;
    cin >> n >> m;
    string s;
    cin >> s;
    ll sn= (int)s.size();
    bool ok = true;
    vector<bool> used(sn+1);
    ll wcnt = 0;
    int acnt = 0;

    for(int i = sn-1;i >= 0;--i){
        if(s[i] == 'W') ++wcnt;
        if(s[i] == 'A') ++acnt;
        if(acnt < wcnt){
            ok = false;
        }
    }

    for(int i = sn-1;i >= 0;--i){
        if(s[i] == 'A'){
            used[i] = true;
            --wcnt;
            if(wcnt == 0) break;
        }
    }

    acnt = 0;
    int ccnt = 0;
    for(int i = 0;i < sn;++i){
        if(s[i] == 'A' && !used[i]) ++acnt;
        if(s[i] == 'C') ++ccnt;

        if(acnt < ccnt){
            ok = false;
        } 
    }

    if(ok){
        cout << "Yes" << endl;
    }
    else{
        cout << "No" << endl;
    }
}