#include <bits/stdc++.h>

using namespace std;

const int N = 400010;
char s[N];

int main()
{
    int n, m;
    scanf("%d%d", &n, &m);
    scanf("%s", s);
    deque<int> a;
    int all = n + n + m + m;
    for (int i = 0; i < all; i++)
    {
        if (s[i] == 'A') a.push_back(i);
    }
    bool ok = true;

    for (int i = 0; i < all; i++)
    {
        char ch = s[i];
        if (ch == 'A') continue;
        int left = i, right = i;
        if (ch == 'C')
        {
            left = a.front();
            a.pop_front();
        }
        else
        {
            right = a.back();
            a.pop_back();
        }

        if (left >= right)
        {
            ok = false;
            break;
        }
    }

    if (ok)
        printf("Yes\n");
    else
        printf("No\n");

    return 0;
}