JAVA过渡学习

package jjava1;
import java.util.Scanner;
public class a2 {
    public static void main(String[] args){
        Scanner l=new Scanner(System.in);
        String a=l.nextLine();
       if(a.equals("加油加油"))System.out.println("YES");
else System.out.println("NO");
    }
}

package jjava1;
import java.util.Scanner;
public class j1 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int i = 0;
        float f = 0.0f;
        System.out.println("请输入整数： ");
        if (scanner.hasNextInt()) {
i=scanner.nextInt();
System.out.println("整数数据"+i);
        }
        else{
            System.out.println("输入的不是整数数据");
        }
     //   Scanner scanner = new Scanner(System.in);
//        int i = 0;
//        float f = 0.0f;
        System.out.println("请输入小数： ");
        if (scanner.hasNextFloat()) {
            f=scanner.nextFloat();
            System.out.println("小数数据"+f);
        }
        else{
            System.out.println("输入的不是小数数据");
        }scanner.close();
    }
}

/*
 实现猜数字的小游戏
 */
import java.util.Random;
import java.util.Scanner;
public class GuessNumber {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    System.out.println("猜数字游戏开始");
    System.out.println("输入1-100之间的数据：");
    //创建Random类变量
    Random ran = new Random();
    int ranNumber = ran.nextInt(100)+1;
    //创建Scanner类变量
    Scanner in = new Scanner(System.in);
    while(true) {
      int number = in.nextInt();
      if(number>ranNumber) {
        System.out.println("您猜测得数字较大，请继续猜测！");
      }else if(number<ranNumber) {
        System.out.println("您猜测得数字较小，请继续猜测！");
      }else {
        System.out.println("恭喜你，猜对了！");
        System.out.println("游戏结束！");
        break;
      }
    }
  }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        //动态创建数组
        int[] arr = new int[sc.nextInt()];//创建数组大小
        for(int i = 0 ; i< arr.length ; i++){
            arr[i]=sc.nextInt();
        }
        int max=maxn(arr);
        System.out.println(max);
    }
    public static int maxn(int []arr){
        int max=0;
        for(int i = 0 ; i< arr.length ; i++){
            if(max<arr[i])max=arr[i];
        }
        return max;
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
      System.out.println("请输入等级");
      char score=sc.next().charAt(0);
      //单个字符输入也可用char c=(char)System.in.read();
      switch(score){
          case 'A':System.out.println("优秀");
          break;
          case 'B':System.out.println("良好");break;
          case'C':System.out.println("及格");
          default:System.out.println("111");
      }
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
      System.out.println("请输入名字");
      String name=sc.nextLine();
      //单个字符输入也可用char c=(char)System.in.read();
      switch(name){
          case "kkk":System.out.println("qqq");
break;
          default:System.out.println("wwww");
      }
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
        int i=0;
    while(i++<=1000){
        if(i%5==0)System.out.print(i+"\t");
        if(i%15==0)System.out.println(i);
    }
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
    for(int i=0;i<=1000;i++){
        if(i%5==0)System.out.print(i+"\t");
        if(i%15==0)System.out.println(i);
    }
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
     for(int i=1;i<=9;i++){
         for(int j=1;j<=i;j++){
             System.out.print(j+"*"+i+"="+(j*i)+"\t");
         }System.out.println();
     }
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
     for(int i=1;i<=9;i++){
         for(int j=1;j<=i;j++){
             System.out.print(j+"*"+i+"="+(j*i)+"\t");
         }System.out.println();
     }
    }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
     int [] numbers={10,20,30,40,50,60,70};
     for(int x:numbers){
         System.out.println(x);
     }
         }
}

package jjava1;
import java.util.Arrays;
import java.util.Scanner;
public class a3 {
    public static void main(String[] args) {
        Scanner kk=new Scanner(System.in);
        int k=kk.nextInt();
        for (int i = 0; i <= k; i++) {
            for(int j=k;j>=i;j--){
                System.out.print(" ");
            }
            for(int j=1;j<=i;j++){
                System.out.print("*");
            }
            for(int j=1;j<i;j++){
                System.out.print("*");
            }
            System.out.println();
        }
     }
    }