1.编写程序, 输入变量x的值,如果是1,输出x=1,如果是5,输出x=5,如果是 10,输出 x=10,除了以上几个值,都输出x=none。(知识点:if条件语句)
package demo3;
import java.util.Scanner;
import java.util.concurrent.SynchronousQueue;
public class day01 {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("请输入变量x的值:");
int x=input.nextInt();
if(x==1)
{
System.out.println("x=1");
}
else if(x==5)
{
System.out.println("x=5");
}
else if(x==10)
{
System.out.println("x=10");
}
else
{
System.out.println("x=none");
}
}
}
![](https://img2020.cnblogs.com/blog/1962549/202003/1962549-20200326111359663-883659932.png)
2.用switch结构实现第1题
package demo3;
import java.util.Scanner;
import java.util.concurrent.SynchronousQueue;
public class day01 {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("请输入变量x的值:");
int x=input.nextInt();
switch(x)
{
case 1:
System.out.println("x=1");
break;
case 5:
System.out.println("x=5");
break;
case 10:
System.out.println("x=10");
break;
default:
System.out.println("x=none");
break;
}
}
}
![](https://img2020.cnblogs.com/blog/1962549/202003/1962549-20200326112517003-743431269.png)
3.判断一个数字是否能被5和6同时整除(打印能被5和6整除),或只能被5整除(打印能被5整 除),或只能被6整除,(打印能被6整除),不能被5或6整除,(打印不能被5或6整除)
package demo3;
import java.util.Scanner;
import java.util.concurrent.SynchronousQueue;
public class day01 {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("请输入变量x的值:");
int x=input.nextInt();
if(x%5==0&&x%6==0)
{
System.out.println("x能被5和6整除");
}
else if(x%5==0&&x%6!=0)
{
System.out.println("x能被5整除但不能被6整除");
}
else if(x%6==0&&x%5!=0)
{
System.out.println("x能被6整除但不能被5整除");
}
else
{
System.out.println("x不能被5和6整除");
}
}
}
![](https://img2020.cnblogs.com/blog/1962549/202003/1962549-20200326114142892-598405481.png)
4.输入一个0~100的分数,如果不是0~100之间,打印分数无效,根据分数等级打印 A(90-100),B(80-89),C,D,E(知识点:条件语句if elseif)
package demo3;
import java.util.Scanner;
import java.util.concurrent.SynchronousQueue;
public class day01 {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("请输入0-100的分数值:");
int x=input.nextInt();
if(x<=100&&x>=90)
{
System.out.println("A");
}
else if(x>=80&&x<=89)
{
System.out.println("B");
}
else if(x>=70&&x<=79)
{
System.out.println("C");
}
else if(x>=60&&x<=69)
{
System.out.println("D");
}
else if(x>=0&&x<=59)
{
System.out.println("E");
}
else
{
System.out.println("违法操作");
}
}
}
![](https://img2020.cnblogs.com/blog/1962549/202003/1962549-20200326120342213-1440212367.png)
5.输入三个整数x,y,z,请把这三个数由小到大输出(知识点:条件语句)
package demo3;
import java.util.Scanner;
import java.util.concurrent.SynchronousQueue;
public class day01 {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("请输入x,y,z的值:");
int x=input.nextInt();
int y=input.nextInt();
int z=input.nextInt();
if(x>y&&x>z)
{
if(y>z)
{
System.out.println(z+"<"+y+"<"+x);
}
else
{
System.out.println(y+"<"+z+"<"+x);
}
}
else if(y>z&&y>x)
{
if(x>z)
{
System.out.println(z+"<"+x+"<"+y);
}
else
{
System.out.println(x+"<"+z+"<"+y);
}
}
else if(z>x&&z>y)
{
if(x>y)
{
System.out.println(y+"<"+x+"<"+z);
}
else
{
System.out.println(x+"<"+y+"<"+z);
}
}
else
{
System.out.println("违法操作");
}
}
}
![](https://img2020.cnblogs.com/blog/1962549/202003/1962549-20200326122852267-1122117262.png)