#include <iostream>
using namespace std;

int main()
{
    string a[6];
    for(int i = 0; i < 6; i++)
    {
        cin >> a[i];
    }
    if(a[0] != a[1] || a[0] != a[2] || a[3] != a[4] || a[3] != a[5])
    {
        cout << "YES" << endl;
    }
    else
    {
        cout << "NO" << endl;
    }
}