class Point {
    public int x;           //定義三點座標
public int y;
    public int z;
//編寫構造器
public Point (int _x, int _y, int _z) {
        x = _x;
y = _y;
z = _z;
}
    //各自設定座標的三個方法
public void setX(int _x) {
        x = _x;
}
    public void setY(int _y) {
        y = _y;
}
    public void setZ(int _z) {
        z
 
= _z;
}
    //計算點到座標原點距離的方法
public void cal() {
        int len = x * x + y * y + z * z;
System.out.println("len = " + len);
}
    //顯示點座標
public void display() {
        System.out.println
                ("x = " + x + " y = " + y + " z = " + z);
}
}


public class Pointf {
    public static void main 
 
(String[] args) {
        Point a1 = new Point (1, 2, 3);
a1.display();
a1.cal();
a1.setX(50);
a1.display();
a1.cal();
a1.setY(50);
a1.setZ(50);
a1.display();
a1.cal();
}
}