java学习(1)
随机数
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   | import java.util.Random; public class Root1{     public static void main(String[] args) {         int[] arr={1,2,3,4,5};         Random r=new Random();         for(int i=0; i< arr.length ;i++)         {             int index=r.nextInt(arr.length);             int temp= arr[i];             arr[i]=arr[index];             arr[index]=temp;         }
          for(int i=0; i<arr.length;i++)         {            System.out.print(arr[i]+" ");          }                      } }
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输出
scanf读入+方法
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   | import java.util.Scanner;
  public class Root2 {     public static void main(String[] args)     {         System.out.println(getSum1(1, 2));         Scanner sc=new Scanner(System.in);         int put=sc.nextInt();         System.out.println(put);         sc.close();     }     public static void getSum(int num1,int num2)     {         int result=num1+num2;         System.out.println(result);         return;     }     public static int getSum1(int num1,int num2)     {         int result=num1+num2;         return result;     } }
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输入
输出
类
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   |  public class Root3 {     public static void main(String[] args)     {         Girlfriend gf1=new Girlfriend();         gf1.name="神里绫华";         gf1.age=21;         gf1.gender="神里家的大小姐";         System.out.println(gf1.name+" "+gf1.age+" "+gf1.gender);         gf1.eat();         gf1.sleep();     } } class Girlfriend {     String name;     int age;     String gender;     public void sleep()     {         System.out.println("女朋友在睡觉");     }     public void eat()     {         System.out.println("女朋友在吃饭");     } }
 
 
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输出
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   | 神里绫华 21 神里家的大小姐 女朋友在吃饭 女朋友在睡觉
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