package com.rk2234;
import java.util.Scanner;
public class ProgramMain {
public static void main(String[] args) {
// TODO Auto-generated method stub
//产生一个输入对象
// Scanner scanner = new Scanner(System.in);
// //输出提示信息
// System.out.println("please input three bit number");
// //定义一个整型变量
// int num;
// //利用输入对象等待用户输入一个值(程序运行到此时就暂停,等待用户输入完毕,按回车键代表输入完毕),保存在名为num的变量中
// num =scanner.nextInt();
// int a= num/100; System.out.println("input three bit number's baiwei is:"+a);
// int b =(num -a*100)/10;
// System.out.println("input three bit number's shiwei is:"+b); int c =num
// -(a*100+b*10); System.out.println("input three bit number's gewei is:"+c);
// int a= num/100;
// System.out.println("input three bit number's baiwei is:"+a);
// int b =(num%100)/10;
// System.out.println("input three bit number's shiwei is:"+b);
// int c =num%10;
// System.out.println("input three bit number's gewei is:"+c);
//displaynumber();
//disFlaotMaxMin();
//dischar();
disString();
}
//定义一个全局变量,整型初始值为0
int valu;
final String name="特烂普and拜死";
public void display() {
int x;
//报错,局部变量,没有默认的初始值
//System.out.println(x);
//valu为全局变量,初始值为0
System.out.println(valu);
//error final定义的变量属于常量变量,值不能变
// name="haobao";
}
public static void displaynumber() {
Scanner scanner = new Scanner(System.in);
Integer value=scanner.nextInt();
char[] chars=value.toString().toCharArray();
for(int i=0;i<chars.length;i=i+1) {
System.out.println(chars[i]);
}
scanner.close();
}
public static void disFlaotMaxMin() {
System.out.println(Float.MAX_VALUE);
System.out.println(Float.MIN_VALUE);
System.out.println(1.4E-1);
float x=(float) 127.0;
System.out.println(x);
}
public static void dischar() {
char val='a';
System.out.println(val);
//强制转换成整型,代表的是这字符在ascii码表中的表示该字的编码数字 a为97 A为65
System.out.println((int)val);
//赋值’字符
val='\'';
System.out.println((int)val);
}
public static void disboolean() {
boolean res=true;
res=false;
System.out.println(res);
}
public static void disString() {
String name="jordan";
String xing=name;
System.out.println(name);
System.out.println(xing);
//String类型是由char变来的,是char数组的表现形式
System.out.println(name.charAt(3));
//StringBuffer是String类型的数组表现形式
StringBuffer sBuffer=new StringBuffer("pipen");
System.out.println(sBuffer);
sBuffer.append(".scot");
System.out.println(sBuffer);
//
//sBuffer="baid";
//原来的值会覆盖
name="baideng";
System.out.println(name);
}
}
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