import std;
import core.bitop;
import core.checkedint;
import core.time;

const dx = [-1, 1, 0, 0];
const dy = [0, 0, -1, 1];

void main() {
	auto s = new string[3];
	foreach(i; 0..3) {
		s[i] = readln.chomp;
	}
	bool ok = true;
	foreach(i; 0..3) {
		foreach(j; 0..3) {
			bool check = true;
			foreach(k; 0..4) {
				const int x = i + dx[k], y = j + dy[k];
				if(range(0, x, 3) && range(0, y, 3)) {
					check &= s[i][j] != s[x][y];
				}
			}
			ok &= check;
		}
	}
	writeln(yes(ok));
}

pragma(inline)
string yes(const bool b) pure @nogc nothrow @safe {
	return b ? "Yes" : "No";
}

pragma(inline)
bool range(const int a, const int x, const int b) pure @nogc nothrow @safe {
	return a <= x && x < b;
}