#include <iostream>
#include <vector>
#include <string>
#include <conio.h>

using namespace std;

int main() {
	string s;
	bool error = false;
	bool ok = false;
	getline(cin, s);

	vector<char> c(5);
	if (s.length() == 5) {
		for (int i = 0; i < 5; i++) {
			c[i] = s[i];
		}
	}
	else error = true;

	if (error == false) {
		if (c[0] < 65 || c[0] > 72) error = true;
		else if (c[1] < 49 || c[1] > 56) error = true;
		else if (c[2] != 45) error = true;
		else if (c[3] < 65 || c[0] > 72) error = true;
		else if (c[4] < 49 || c[4] > 56) error = true;
	}

	if (error == false) {
		if (abs(c[0] - c[3]) == 1 && abs(c[1] - c[4]) == 2) ok = true;
		else if (abs(c[0] - c[3]) == 2 && abs(c[1] - c[4]) == 1) ok = true;
	}

	if (error == false) {
		if (ok == true) cout << "YES";
		else cout << "NO";
	}
	else cout << "ERROR";

	_getch();
	return 0;
}