N,M=map(int,input().split())
S=input()
W,A,C=[],[],[]
for i in range(2*N+2*M):
    if S[i]=="W":
        W.append(i)
    if S[i]=="A":
        A.append(i)
    if S[i]=="C":
        C.append(i)
if all(i<j for i,j in zip(W,A[N:])) and all(i<j for i,j in zip(A[:N],C)):
    ans="Yes"
else:
    ans="No"
print(ans)