import sys
sys.setrecursionlimit(5*10**5)
input = sys.stdin.readline
from collections import defaultdict, deque, Counter
from heapq import heappop, heappush
from bisect import bisect_left, bisect_right
from math import gcd

n,m = map(int,input().split())
s = input().rstrip()


def f():
  quea = deque([])
  quew = deque([])
  for i,c in enumerate(s):
    if c == "A":
      quea.append(i)
    elif c == "C":
      if not quea:
        return False
      else:
        quea.popleft()
    else:
      quew.append(i)

  while quew:
    la = quea.popleft()
    lw = quew.popleft()
    if la < lw:
      return False
  return True

print('Yes') if f() else print('No')