JAVA上机考试常出现的十道编程题
常用十题
1、九九乘法表：
public class chengfa {
public static void main(String[] args) {
int i,j;
System.out.println("9*9乘法表如下：");
for(i=1;i<=9;i++)
{
for(j=1;j<=i;j++)
{
System.out.print(+i+"*"+j+"="+i*j);
System.out.print(" " );
}
System.out.println( );
}
}
}
2、成绩判断
import java.util.Scanner;
public class chengjipanduan {
public static void main(String[] args) {
int grade;
System.out.println(" 输入你的成绩：");
Scanner s=new Scanner(System.in);
grade=s.nextInt();
switch(grade/10)
{
case 10:
case 9:
System.out.println(" 你的成绩为优");break;
case 8:
System.out.println(" 你的成绩为良");break;
case 7:
System.out.println(" 你的成绩为中");break;
case 6:
System.out.println(" 你的成绩为及格");break;
case 5:
case 4:
case 3:
case 2:
case 1:
case 0:
System.out.println(" 你的成绩为差");break;
}
}
}
3、矩形类
public class Rectangle {
double width=1.0;
double height=1.0;
public Rectangle(double width,double height)
{
this.width=width;
this.height=height;
}
public void setwidth(double width)
{
this.width=width;
}
public double getwidth(double widtht)
{
return width;
}
public void setheight(double height)
{
this.height=height;
}
public double getheight(double height)
{
return height;
}
public double getArea()
{
return width*height;
}
public double getperimeter()
{
return 2*(width+height);
}
}
import tixing06.Rectangle;
public class TestRectangle {
public static void main(String[] args)
{
Rectangle r=new Rectangle(4,40);
System.out.println(" 矩形面积为 "+r.getArea()+" 周长为 "+r.getperimeter());
}
}
4、两数对换
package tixing;
import java.util.Scanner;
public class TiXing02 {
public static void main(String[] args) {
int a,b;
System.out.println(" 输入两个数 a 和 b:");
Scanner s=new Scanner(System.in);
a=s.nextInt();
Scanner k=new Scanner(System.in);
b=k.nextInt();
System.out.println(" 两个数为 :a="+a+" b="+b);
exchange(a,b);
}
public static void exchange(int a,int b)
{
int t;
t=a;a=b;b=t;
System.out.println(" 交换后两个数为:a="+a +" b="+b);
}
}
5、数组
import java.util.Scanner;
import java.util.Random;
public class shuzu {
public static void main(String[] args) {
int n,i,j,k;
double ave=0;
System.out.println(" 输入数组长度：");
Scanner s=new Scanner(System.in);
n=s.nextInt();
int a[]=new int[n];
System.out.println(" 输入的原数组为：");
for(i=0;i { a[i]=(int)(Math.random()*10+1); System.out.printf("%4d",a[i]); } for(i=0;i for(j=i+1;j { if(a[j]>a[i]) { k=a[i];a[i]=a[j];a[j]=k; } } } System.out.println(); System.out.println("输入的数组排序为："); for(i=0;i { System.out.printf("%4d",a[i]); } int max,min; max=a[0];min=a[0]; for(i=0;i { if(a[i]>max) { max=a[i]; } if(a[i] { min=a[i]; } ave+=a[i]; } System.out.println(); System.out.println(" System.out.println(" System.out.println("数组中最大数为： 数组中最小数为： 数组中平均数为： "+max); "+min); "+ave/n); } } 6、填充圆 package tianchongyuan; import java.applet.*; import java.awt.*; public class TianChongY uan extends Applet{ public void paint(Graphics g) { g.drawOval(0,0,100,100); g.drawRoundRect(110,10,90,60,50,30); g.setColor(Color.blue); g.fillArc(0,0,100,100,0,360); g.setColor(Color.red); g.fillArc(110,10,90,60,0,360); } 7、星形三角形 package sanjiaoxing; import java.util.Scanner; public class SanJiaoXing { public static void main(String[] args) { int i,j,n; System.out.println(" 输入层数n:"); Scanner s=new Scanner(System.in); n=s.nextInt(); for(i=1;i<=n;i++) { for(j=0;j { System.out.printf(" "); } if(i%2!=0) { for(j=0;j<2*i-1;j++) { System.out.printf("*"); } System.out.println(""); } else { System.out.printf("*"); for(j=0;j<2*i-3;j++) { System.out.printf(" "); } System.out.printf("*"); System.out.println(""); } } } 8、一元二次 import java.util.Scanner; public class yiyuanerci { public static void main(String[] args) { double a,b,c,m; double x1,x2; System.out.println(" 输入一元二次方程前的三个系数a,b,c:"); Scanner s=new Scanner(System.in); a=s.nextDouble(); Scanner sc=new Scanner(System.in); b=sc.nextDouble(); Scanner sr=new Scanner(System.in); c=sr.nextDouble(); m=b*b-4*a*c; if(m>0) { System.out.println("两根为x1="+(-b+Math.sqrt(m))/(2*a)+" x2="+(-b-Math.sqrt(m))/(2*a)); } else if(m==0) { System.out.println(" 方程有同根为:x1=x2="+(-b/(2*a))); } if(m<0) { System.out.println(" 方程无根 "); } } } 9、平方根 import java.util.Scanner; public class pingfanggeng { public static void main(String[] args) { int a,b,c,m; double x1,x2; Scanner sc=new Scanner(System.in); System.out.println(" 请输入一元二次方程的二次项系数：a=sc.nextInt(); Scanner sr=new Scanner(System.in); System.out.println(" 请输入一元二次方程的一次项系数：b=sr.nextInt(); Scanner st=new Scanner(System.in); System.out.println(" 请输入一元二次方程的常数项系数："); "); "); c=st.nextInt(); m=b*b-4*a*c; x1=(-b+Math.sqrt(m))/(2*a); x2=(-b-Math.sqrt(m))/(2*a); System.out.println(" 一元二次方程的根为： "+x1+""+x2); } } 10、简单计算机窗口（此题为JFrame 窗体） import javax.swing.JOptionPane; public class NewJFrame extends javax.swing.JFrame { public NewJFrame() { initComponents(); } private void initComponents() { jLabel1 = new javax.swing.JLabel(); jLabel2 = new javax.swing.JLabel(); jTextField1 = new javax.swing.JTextField(); jTextField2 = new javax.swing.JTextField(); jButton1 = new javax.swing.JButton(); jButton2 = new javax.swing.JButton(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); jLabel1.setText(" 第一个数 "); jLabel2.setText(" 第二个数 "); jTextField1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jTextField1ActionPerformed(evt); } }); jTextField2.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jTextField2ActionPerformed(evt); } }); jButton1.setText(" 计算 "); jButton1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton1ActionPerformed(evt); } }); jButton2.setText(" 取消 "); jButton2.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton2ActionPerformed(evt); } }); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(49, 49, 49) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignm ent.LEADING) .addGroup(layout.createSequentialGroup() .addGroup(layout.createParallelGroup(javax.swing.GroupLayou t.Alignment.LEADING) .addComponent(jLabel2) .addComponent(jLabel1)) .addGap(82, 82, 82) .addGroup(layout.createParallelGroup(javax.swing.GroupLayou t.Alignment.LEADING, false) .addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 75, javax.swing.GroupLayout.PREFERRED_SIZE) .addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE, 75, javax.swing.GroupLayout.PREFERRED_SIZE))) .addGroup(layout.createSequentialGroup() .addComponent(jButton1) .addGap(125, 125, 125) .addComponent(jButton2))) .addContainerGap(112, Short.MAX_V ALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(31, 31, 31) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignm ent.BASELINE) .addComponent(jLabel1) .addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE,javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGap(35, 35, 35) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignm ent.BASELINE) .addComponent(jLabel2) .addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE,javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGap(40, 40, 40) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignm ent.BASELINE) .addComponent(jButton1) .addComponent(jButton2)) .addContainerGap(129, Short.MAX_V ALUE)) ); pack(); } private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) { } private void jTextField2ActionPerformed(java.awt.event.ActionEvent evt) { } private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { double qiuhe; qiuhe = Double.parseDouble(jTextField1.getText()) + Double.parseDouble(jTextField2.getText()); JOptionPane.showMessageDialog(null,qiuhe); } private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) { dispose(); System.exit(0); // TODO add your handling code here: } public static void main(String args[]) { /* Set the Nimbus look and feel */ // /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see https://www.360docs.net/doc/3c12151777.html,/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for(javax.swing.UIManager.LookAndFeelInfo info: javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (ClassNotFoundException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level. SEVERE, null, ex); } catch (InstantiationException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level. SEVERE, null, ex); } catch (IllegalAccessException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level. SEVERE, null, ex); } catch (javax.swing.UnsupportedLookAndFeelException ex) { java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level. SEVERE, null, ex); } // /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new NewJFrame().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JButton jButton1; private javax.swing.JButton jButton2; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JTextField jTextField1; private javax.swing.JTextField jTextField2; // End of variables declaration }