#include <iostream>
#include <string>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <map>
#include <cmath>
#include <queue>
#include <utility>
#include <functional>
#include <deque>
#include <cctype>
#include <stack>
#include <bitset>
#include <set>

using ll = long long;
using namespace std;
typedef unsigned long long ull;
typedef pair<ll, ll>P;

const ll MOD = 1000000007;
const ll INF = 1 << 30;
const ll INF2 = 9000000000000000000LL;
const int dx[4] = { 1,0,-1,0 }, dy[4] = { 0,1,0,-1 };
const int tx[8] = { -1,0,1,-1,1,-1,0,1 }, ty[8] = { -1,-1,-1,0,0,1,1,1 };
#define ALL(x) (x).begin(),(x).end()

int main(){
    int n,m;
    cin>>n>>m;
    string s;
    for(int i=0;i<n;i++){
        cin>>s;
        for(int j=0;j<m-4;j++){
            if(s.substr(j,4)=="LOVE"){
                cout<<"YES"<<endl;
                return 0;
            }
        }
    }
    cout<<"NO"<<endl;
    return 0;
}