# 第二次作业

1.  定义圆的半径，求圆面积

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
int r=2;
double s=3.14*r*r;
System.out.println("圆面积为"+s);

}

}

2.华氏度摄氏度的转换

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner in=new Scanner(System.in);
float C;
float F=in.nextInt();
C=(F-32)*5/9;
System.out.println("摄氏度为"+C);

}

}

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner in=new Scanner(System.in);
float F;
float C=in.nextInt();
F=C*9/5+32;
System.out.println("华氏度为"+F);

}

}

3.a,b两个变量中的值互换

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
int a=5;
int b=8;
int c=a;
a=b;
b=c;
System.out.println("a="+a+" "+"b="+b);

}

}

4.将五位整数保留到百位

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
int a=12345;
int b=a/100*100;
System.out.println(b);

}

}

5.求各位数的和

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
int a=685;
int ge=a%10;
int shi=a%100/10;
int bai=a/100;
int sum=ge+shi+bai;
System.out.println("各位数的和为"+sum);

}

}

6.大写小写字母转换

import java.util.Scanner;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
char a='A';
System.out.println((char)(a+32));
char A='a';
System.out.println((char)(A-32));
}

}

posted @ 2021-03-12 09:40  刘源丰  阅读(46)  评论(0编辑  收藏  举报