import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int t = Integer.parseInt(br.readLine());
		PrintWriter pw = new PrintWriter(System.out);
		for (int z = 0; z < t; z++) {
			String x = br.readLine();
			String y = br.readLine();

			if (x.length() == y.length()) {
				if (x.compareTo(y) > 0) {
					pw.println("X");
				} else {
					pw.println("Y");
				}
			} else {
				StringBuilder sbx = new StringBuilder(x);
				StringBuilder sby = new StringBuilder(y);
				sbx.append(x);
				sby.append(y);
				while (sbx.length() < sby.length()) {
					sbx.append(x);
				}
				while (sbx.length() > sby.length()) {
					sby.append(y);
				}

				String x2 = sbx.toString();
				String y2 = sby.substring(0, x2.length());
				int cmp = x2.compareTo(y2);
				if (cmp == 0) {
					if (x.length() > y.length()) {
						pw.println("X");
					} else {
						pw.println("Y");
					}
				} else if (cmp > 0) {
					pw.println("X");
				} else {
					pw.println("Y");
				}
			}
		}
		pw.flush();
		br.close();
	}
}