1 /******************************************
2 * 这是演示JAVA应用
程序结构的一个简单例子 *
3 * 该文件名是 Welcome.java *
4 ******************************************/
5 class Welcome
6 {
7 public static void main(String[] args)
8 {
9 System.out.println("欢迎使用JAVA编程!"); //显示“欢迎使用JAVA编程!”
10 }
11 }
**********************************************************
// exp1_2.java
class exp1_2
{
public static void main(String[] args)
{
int n; //声明一个名为n的整型变量
n=15; //给变量赋15
System.out.println(n); //在屏幕上显示变量n的值
//在屏幕上显示一个字符串及n的平方值
System.out.println("n的平方值是:"+n*n);
}
}
*********************************************************************
class exp_string
{
public static void main(String[] args)
{
System.out.println("wn\u04305f\\\nu0x\ty");
System.out.println("----------------------");
System.out.println("b\bt\"\u007g\\u0042\tr\nn\u0630j");
}
}
*******************************************************************
class exp_char_num
{
public static void main(String[] args)
{
System.out.println("'A'+1="+('A'+1));
System.out.println("'1'+1="+('1'+1));
System.out.println("1+1="+(1+1));
}
}
*********************************************************************
class exp_operater
{
public static void main(String[] args)
{
int a=63, b=48;
double i=3.1415, j=4.11;
System.out.println("a+b="+(a+b));
System.out.println("a-b="+(a-b));
System.out.println("a*b="+(a*b));
System.out.println("a/b="+(a/b));
System.out.println("a%b="+(a%b));
System.out.println("i+j="+(i+j));
System.out.println("i-j="+(i-j));
System.out.println("i*j="+(i*j));
System.out.println("i/j="+(i/j));
System.out.println("i%j="+(i%j));
System.out.println("a+j="+(a+j));
System.out.println("i*b="+(i*b));
System.out.println("字母A的后继字母是"+(char)('A'+1));
}
}
********************************************************************
//"System.in.read()"练习
package in_out;
//import java.io.*;
public class Program
{
public static void main(String[] args)throws java.io.IOException
{
//基本演示
char ch;
System.out.print("请输入一个字符:\t");
ch = (char)System.in.read();
System.out.println("您输入的字符是:\t" + ch);
//
演示int、ctrl+z
//int i;
//System.out.print("请输入一个字符:\t");
//i= System.in.read();
//System.out.println("您输入的字符是:\t" + i);
//演示键盘输入与缓冲区
//char ch1,ch2,ch3,ch4,c
h5;
//System.out.print("请输入一行字符(至少5个):\t");
//ch1= (char)System.in.read();
//ch2= (char)System.in.read();
//ch3= (char)System.in.read();
//ch4= (char)System.in.read();
//ch5= (char)System.in.read();
//System.out.println("您输入的一行字符中,前5个字符是:\t" + ch1 + "," + ch2 + "," + ch3 + "," + ch4 + "," +ch5);
//System.out.println("您输入的一行字符中,前5个字符的代码是:\t" + (int)ch1 + "," + (int)ch2 + "," + (int)ch3 +","+(int)ch4 +","+(int)ch5);
}
}
############################################################################
//表达式与类"MATH"练习;
import java.io.*;
/**
* Summary description for Program
*/
public class Program
{
public static void main(String[] args)throws java.io.IOException
{
int i, j;