#include <bits/stdc++.h>
#define INF 990000000
//27
using namespace std;

int main() {
int n,m;
cin>>n>>m;

int res=0;

for(int i=0;i<n;i++){
string s;
cin>>s;
if(s.find("LOVE")!=string::npos)res++;
}
if(res>0)
cout << "YES"<<endl;
else
cout << "NO"<<endl;





}