/* -*- coding: utf-8 -*-
 *
 * 2240.cc:  No.2240 WAC - yukicoder
 */

#include<cstdio>
#include<vector>
#include<algorithm>

using namespace std;

/* constant */

const int MAX_N = 100000;
const int MAX_M = 100000;
const int MAX_L = (MAX_N + MAX_M) * 2;

/* typedef */

typedef vector<int> vi;

/* global variables */

char s[MAX_L + 4];

/* subroutines */

/* main */

int main() {
  int n, m;
  scanf("%d%d%s", &n, &m, s);
  int l = (n + m) * 2;

  vi wv, av, cv;
  for (int i = 0; i < l; i++) {
    if (s[i] == 'W') wv.push_back(i);
    else if (s[i] == 'A') av.push_back(i);
    else cv.push_back(i);
  }

  for (int i = 0; i < n; i++)
    if (wv[i] > av[m + i]) { puts("No"); return 0; }
  for (int i = 0; i < m; i++)
    if (av[i] > cv[i]) { puts("No"); return 0; }

  puts("Yes");
  return 0;
}