电脑
1百分制分数到等级分数package pm; public class SwitchTest {//编写程序，实现从百分制分数到等级分数的转换 ////>=90 A// 80~89 B// 70~79 C// 60~69 D// <60 E public static void main(String[] args) {int s=87;switch(s/10){ case 10 :System.out.println('A');break; case 9 :System.out.println('A');break; case 8 :System.out.println('B');break;case 7 :System.out.println('c');break;case 6 :System.out.println('D');break;default :System.out.println('E');break; }} }
2成法口诀阵形package pm; public class SwitchTest{public static void main(String[] args){ for(int i=1;i<=9;i++){ for(int j=1;j<=i;j++){ System.out.print(j+'*'+i+'='+(i*j)+'\t'); } System.out.println(); }}}
3华氏和摄氏的转换法 package pm;import java.util.Scanner;public class SwitchTest {public static void main(String[] args) { Scanner sc=new Scanner(System.in);while (true) {System.out.println('请输入要转换的温度类型：C 或 F');String s = sc.next().trim();if ('c'.equalsIgnoreCase(s)) {//做摄氏向华摄的转换System.out.println('请输入要转换摄氏的温度:..');double db = sc.nextDouble();double db2 = (db * 9 / 5) + 32;System.out.println('对应的华氏温度：' + db2 + 'F');} else if ('f'.equalsIgnoreCase(s)) {//做华摄向摄氏的转换System.out.println('请输入要转换华氏的温度:..');double db = sc.nextDouble();double db2 = (db - 32) * 5 / 9;System.out.println('对应的摄氏温度：' + Math.round(db2) + 'C');}else if('exit'.equalsIgnoreCase(s)){break;}}} } package pm; import java.util.Scanner; public class SwitchTest{public static void main(String[] args) {Scanner sc=new Scanner(System.in);boolean flag=true;while (flag) {System.out.println('请输入要转换的温度,如：50c或100f');String str = sc.nextLine().trim();if (str.endsWith('c') || str.endsWith('C')) {//做摄氏向华摄的转换 30cString st = str.substring(0, str.length() - 1);double db = Double.parseDouble(st);//[0,2)//2 double db=Double.valueOf(st).doubleValue();double db2 = (db * 9 / 5) + 32;System.out.println('对应的华氏温度：' + db2 + 'F');} else if (str.endsWith('f') || str.endsWith('F')) {//做华摄向摄氏的转换 String st = str.substring(0, str.length() - 1);double db = Double.parseDouble(st);//[0,2)//2 double db=Double.valueOf(st).doubleValue();double db2 = (db - 32) * 5 / 9;System.out.println('对应的摄氏温度：' + Math.round(db2) + 'C');}else if('exit'.equalsIgnoreCase(str)){flag=false;}}}}
4三个数的最大数package pm; public class SwitchTest {public static void main(String[] args) {int a=1,b=2,c=3,d=0;d=a>b?a:b;d=a>b?(a>c?a:c):(b>c?b:c);System.out.println('最多数为：'+d);} }
5简单计算器的小程序 package one; import java.awt.BorderLayout;import java.awt.GridLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener; import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JTextField; public class Jsq implements ActionListener { private JFrame frame; private JButton[] bus; private JTextField jtx; private JButton bu; private char[] strs; private String d_one = ''; private String operator; public static void main(String[] args) {new Jsq();} /* 利用构造进行实例化 */public Jsq() {frame = new JFrame('计算器');jtx = new JTextField(14);bus = new JButton[16];strs = '789/456*123-0.+='.toCharArray();for (int i = 0; i < 16; i++) {bus[i] = new JButton(strs[i] + '');bus[i].addActionListener(this);}bu = new JButton('C');bu.addActionListener(this);init();} /* GUI 初始化 */public void init() {JPanel jp1 = new JPanel();jp1.add(jtx);jp1.add(bu);frame.add(jp1, BorderLayout.NORTH); JPanel jp2 = new JPanel();jp2.setLayout(new GridLayout(4, 4));for (int i = 0; i < 16; i++) {jp2.add(bus[i]);} frame.add(jp2, BorderLayout.CENTER); frame.pack();frame.setLocation(300, 400);frame.setVisible(true);frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } /* 事件的处理 */ public void actionPerformed(ActionEvent arg0) {/*获取输入字符*/String conn = arg0.getActionCommand();/*清除计算器内容*/if ('C'.equals(conn)) {d_one = '';operator = '';jtx.setText('');return;}/*暂未实现该功能*/if('.'.equals(conn)){return;}/*记录运算符，保存运算数字*/if (('+-*/'.indexOf(conn)) != -1) {if(''.equals(d_one) && ''.equals(jtx.getText())) return;d_one = jtx.getText();operator = conn;jtx.setText('');return;}/*计算结果*/if ('='.equals(conn)) {if(''.equals(d_one) && ''.equals(jtx.getText())) return;double db = 0;if ('+'.equals(operator)) {db = Double.parseDouble(d_one)+ Double.parseDouble(jtx.getText());jtx.setText(db + '');}if ('-'.equals(operator)) {db = Double.parseDouble(d_one)- Double.parseDouble(jtx.getText());jtx.setText(db + '');}if ('*'.equals(operator)) {db = Double.parseDouble(d_one)* Double.parseDouble(jtx.getText());jtx.setText(db + '');}if ('/'.equals(operator)) {db = Double.parseDouble(d_one)/ Double.parseDouble(jtx.getText());jtx.setText(db + '');}d_one = db + '';return;}//界面显示jtx.setText(jtx.getText() + conn); } }
6三角形图案 package pm; public class SwitchTest{public static void main(String[] args){ int n=5; for(int i=0;i<=n;i++){ for(int j=0;j
7输出输入的姓名 package pm;import java.util.Scanner;public class SwitchTest{public static void main(String[] args){ String name=null; Scanner sca=new Scanner (System.in); char firstChar; do{ System.out.println('please input your name'); name=sca.nextLine(); firstChar=name.charAt(0); }while(!(firstChar>='a' && firstChar<='z' || firstChar>='A' && firstChar<='Z')); System.out.println('OK! your name is:'+name); }}
8一小时倒计时小程序 package pm; import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel; public class SwitchTest {private JFrame frame;private JLabel jl1;private JLabel jl2;private JLabel jl3;/*主方法*/public static void main(String[] args) {new SwitchTest().getTime();}/*倒计时的主要代码块*/private void getTime(){long time=1*3600;long hour =0 ;long minute =0 ;long seconds=0;while(time>=0){hour=time/3600;minute=(time-hour*3600)/60;seconds=time-hour*3600-minute*60;jl1.setText(hour+'时');jl2.setText(minute+'分');jl3.setText(seconds+'秒');try {Thread.sleep(1000);} catch (InterruptedException e) {e.printStackTrace();}time--;}}/*构造 实现界面的开发 GUI */public SwitchTest(){frame = new JFrame('倒计时');jl1 = new JLabel();jl2 = new JLabel();jl3 = new JLabel();init();}/*组件的装配*/private void init(){JPanel jp=new JPanel();jp.add(jl1);jp.add(jl2);jp.add(jl3);frame.add(jp);frame.setVisible(true);frame.setLocation(300,400);frame.setSize(300, 200);frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);} }
9棋盘图案 public class Sjx{public static void main(String[] args){ int SIZE=19; for(int i=0;i
10数组输出唐诗package day04; public class ArrayTest { public static void main(String[] args){ char[][] arr=new char[4][7]; String s='朝辞白帝彩云间千里江陵一日还两岸猿声啼不住轻舟已过万重山'; for(int i=0;i
11找出满足条件的最小数 package day02;public class Fangk{public static void main(String[] args){// for(int i=1000;i<=9999;i++){// int q=i/1000;// int b=i/100%10;// int s=i/10%10;// int g=i%10;// if(q>b && s>g && q+g==b+s && b%2!=0){// System.out.println('The Min Number is:'+i);// break;// }// }loop1: for(int q=1;q<=9;q++){loop2: for(int b=0;b<=9;b++){ if(b%2==0){ continue loop2; }for(int s=0;s<=9;s++){for(int g=0;g<=9;g++){if(q>b && s>g && q+g==b+s){System.out.println('The Min Number is:'+(q*1000+b*100+s*10+g));break loop1;}}}}}}}
12判断一个数是否是素数 package day02;public class Fangk{public static void main(String[] args){int num=14;boolean flag=true;for(int i=2;i<=num/2;i++){if(num%i==0){flag=false;break;}}if(flag){System.out.println(num+' is a prime number!');}else{System.out.println(num+' is not a prime number!');}}} //////////////////////////////////////////////////////////////////////package day04;import java.util.Scanner; public class A1{ public static void main(String[] args){ int n; Scanner sca=new Scanner(System.in); System.out.println('please input a number:'); n=sca.nextInt(); if(isPrimeNumber(n)){ System.out.println(n+'is a prime number!'); }else{ System.out.println(n+'is not a prime number!'); } } public static boolean isPrimeNumber(int n){ for(int i=2;i<=n/2;i++){ if(n%i==0){ return false;} }return true; }}
12判断一个数是否是素数 package day02;public class Fangk{public static void main(String[] args){int num=14;boolean flag=true;for(int i=2;i<=num/2;i++){if(num%i==0){flag=false;break;}}if(flag){System.out.println(num+' is a prime number!');}else{System.out.println(num+' is not a prime number!');}}} //////////////////////////////////////////////////////////////////////package day04;import java.util.Scanner; public class A1{ public static void main(String[] args){ int n; Scanner sca=new Scanner(System.in); System.out.println('please input a number:'); n=sca.nextInt(); if(isPrimeNumber(n)){ System.out.println(n+'is a prime number!'); }else{ System.out.println(n+'is not a prime number!'); } } public static boolean isPrimeNumber(int n){ for(int i=2;i<=n/2;i++){ if(n%i==0){ return false;} }return true; }}
14将一个整数以二进制输出 package day04; import java.util.Scanner; public class ArrayTest { public static void main(String[] args){ int n; Scanner s=new Scanner(System.in); System.out.println('please input a number:'); n=s.nextInt(); for(int i=31;i>=0;i--){ if((n&(1<
15矩形图案 package day02; public class Fangk {public static void main(String[] args){int m=5,n=6;for(int i=0;i
1.滴水穿石，非一日之功，多练习，多反省。