JAVA科学计算器代码如何编答:import java.awt.*;import java.awt.event.*;import java.lang.*;import javax.swing.*;public class Counter extends Frame { //声明三个面板的布局 GridLayout gl1,gl2,gl3;Panel p0,p1,p2,p3;JTextField tf1;TextField tf2;Button b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,...