// SubOne.java
public class SubOne {
	public static void main(String[] args) {
		int x1=3;
		int x2=3;
		// --ں
		int y1 = x1--;
		// --ǰ
		int y2 = --x2;
		System.out.println("y1="+y1+" y2="+y2);
	}
}