efg1111

#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
int main() {
    string s;
    cin >> s;
    char a,b;
    a=s[0];
    b=s[3];
    int a1=int(a)-64, b1=int(b)-64;
    if (abs(a1-b1)==2 and abs(int(s[1]-s[4]))==1 or abs(a1-b1)==1 and abs(int(s[1]-s[4])==2)) cout << "YES";
    else if (s.size()<5 or isalpha(s[0])== false or s[2]!='-' or isdigit(s[1])==false or isalpha(s[3])==false or
            isdigit(s[4])==false) cout << "ERROR";
    else cout << "NO";
}