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

int main()
{
    int N, M;
    string S;
    cin >> N >> M >> S;

    vector<int> indexW;
    vector<int> indexA;
    vector<int> indexC;

    for (int i = 0; i < 2 * (N + M); i++)
    {
        if (S[i] == 'W')
        {
            indexW.push_back(i);
        }
        else if (S[i] == 'A')
        {
            indexA.push_back(i);
        }
        else
        {
            indexC.push_back(i);
        }
    }

    for (int i = 0; i < N; i++)
    {
        if (indexW[i] > indexA[i + M])
        {
            cout << "No" << endl;
            return 0;
        }
    }
    for (int i = 0; i < M; i++)
    {
        if (indexA[i] > indexC[i])
        {
            cout << "No" << endl;
            return 0;
        }
    }
    cout << "Yes" << endl;
}