#include<iostream>
#include<queue>
using namespace std;
string S;
int N,M;
bool used[4<<17];
int main()
{
	cin>>N>>M>>S;
	queue<int>Q;
	for(int i=0;i<S.size();i++)
	{
		if(S[i]=='A')
		{
			Q.push(i);
		}
		else if(S[i]=='C')
		{
			if(Q.empty())
			{
				cout<<"No"<<endl;
				return 0;
			}
			used[Q.front()]=true;
			Q.pop();
		}
	}
	while(!Q.empty())Q.pop();
	for(int i=0;i<S.size();i++)if(!used[i])
	{
		if(S[i]=='W')
		{
			Q.push(i);
		}
		else if(S[i]=='A')
		{
			if(Q.empty())
			{
				cout<<"No"<<endl;
				return 0;
			}
			Q.pop();
		}
	}
	cout<<"Yes"<<endl;
}