#include<iostream>
#include<string>
#include<algorithm>
using namespace std;
int main(){
int a,b,ans=0;
char aa[50][50];
cin>>a>>b;
for(int i=0;i<a;i++){
	for(int j=0;j<b;j++){
		cin>>aa[i][j];
	}
}
for(int i=0;i<a;i++){
	for(int j=0;j<b;j++){
		if(aa[i][j]=='L'&& aa[i][j+1]=='O' &&aa[i][j+2]=='V' && aa[i][j+3]=='E'){
			ans++;
		}
	}
}
if(ans>0){
	cout<<"Yes"<<endl;
}else{
	cout<<"No"<<endl;
}
}