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

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int N,M;
	string S;
	cin >> N >> M >> S;
	int cnt = 2*N+2*M;
	vector<int>sum(cnt+1),sum2(cnt+1);
	for(int i = 0; i < cnt; i++) {
		sum[i+1] = sum[i]+(S[i] == 'A');
	}
	for(int i = cnt-1; i >= 0; i--) {
		sum2[i] = sum2[i+1]+(S[i] == 'A');
	}
	int res = 0;
	for(int i = cnt-1; i >= 0; i--) {
		if(S[i] == 'W') res++;
		if(res > sum2[i]) {
			cout << "No" << "\n";
			return 0;
		}
	}
	res = 0;
	for(int i = 0; i < cnt; i++) {
		if(S[i] == 'C') res++;
		if(res > sum[i]) {
			cout << "No" << "\n";
			return 0;
		}
	}
	cout << "Yes" << "\n";
}