第六次作业

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int sum = 0;
        for (int i = 0; i <= 100; i++) {
            if ((i % 10) != 3)
                sum += i;
        }
        System.out.println(sum);
    }

}

第二题

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < -2 * i + 8; j++) {
                System.out.print(" ");
            }
            for (int k = 0; k < (2 * i + 1); k++) {
                System.out.print("* ");
            }
            System.out.println();
        }

    }

}

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < 5-i; j++) {
                System.out.print("*");
            }

            System.out.println();
        }

    }

}

第三题

import java.util.Scanner;

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入学生姓名");
        while (true) {
            String name = sc.nextLine();
            if ("Q".equals(name)) {
                System.out.println("程序结束");
                break;
            }
            System.out.println("请输入学生姓名");

        }

    }

}

第四题

import java.util.Scanner;

public class Exe01 {

    /**
     * @param args
     * @return 
     */
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        // TODO Auto-generated method stub
        int sum = 0;
        for (int i = 0; i < 5; i++) {

            System.out.print("请输入第" + (i + 1) + "个学生的成绩");
            int a = sc.nextInt();
            if (a > 100 || a < 0) {
                System.out.println("输入错误，重新输入");
                a = sc.nextInt();
            }
            sum += a;
        }
        System.out.println(sum);
    }

}

第五题

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int i = 1;
        double fenzi = 1;
        double fenmu = 0;
        double fenshu = fenzi / fenmu;
        double sum = 0;
        for (i = 1; i < 11; i++) {
            fenmu += i;
            fenshu = fenzi / fenmu;
            sum += fenshu;
        }
        System.out.println("和为" + sum);

    }

}

作业一

import java.util.Random;
import java.util.Scanner;


public class TEXT1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
          Scanner input=new Scanner(System.in);
          Random r=new Random();
          int a = r.nextInt(99);
          int i=1;
          System.out.println("输入1-99之间数");
          for (i=1;i<=99;i++){
              int b=input.nextInt();
              if (b>i){
                  System.out.println("大了点");
                  continue;
              }if (b<i){
                  System.out.println("小了点");
                  continue;
              }else
                  System.out.println("猜对了");
                  break;
              }
       }

}

作业二

import java.util.Scanner;


public class TEXT1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("请输入一个整数（大于等于2）");
        int a=input.nextInt();
        boolean prime=true;
        for (int i=2;i<a;i++){
            if (a%i==0){
                prime=false;
                break;
            }
        }if(prime){
            System.out.println("是质数");
        }else{
            System.out.println("不是质数");
        }
    }

}

作业三

public class TEXT1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
       int a=1,b=1,c=0;
       for (int i=1;i<=18;i++){
           c=a+b;
           a=b;
           b=c;
       }System.out.println("斐波那契数列的第20项是："+c);
    }

}