#include<stdio.h>
char s[400005];
int main()
{
	int n, m;
	scanf("%d %d", &n, &m);
	scanf("%s", s);
	int i, cnt;
	for (cnt = 0, i = 0; i < 2 * n + 2 * m; i++)
	{
		if (s[i] == 'A')
			cnt++;
		if (s[i] == 'C')
		{
			if (cnt == 0)
			{
				printf("No\n");
				return 0;
			}
			cnt--;
		}
	}
	for (cnt = 0, i = 2 * n + 2 * m - 1; i >= 0; i--)
	{
		if (s[i] == 'A')
			cnt++;
		if (s[i] == 'W')
		{
			if (cnt == 0)
			{
				printf("No\n");
				return 0;
			}
			cnt--;
		}
	}
	printf("Yes\n");
	return 0;
}