#include<bits/stdc++.h>
using namespace std;

int main(){
	int n;
	string s;
	
	cin >> n >>s;
	vector<string>ss{"wa","wo","n","?a","?o","w?","?"};
	for(auto &cs:ss){
		auto sp=s.find(cs);
		while(sp!=string::npos){
			s.erase(sp,cs.size());
			sp=s.find(cs);
		}
	}
	if(s.empty()){
		cout<<"Yes"<<endl;
	}
	else{
		cout<<"No"<<endl;
	}
	
	
}