JAVA编程语言基础第六章

上机练习1
package tz1;

public class dome1 {
public static void main(String[] args) {

      int sum=0;
      for (int num =1; num<=99; num+=2) {
       sum+=num;
       System.out.println(sum);
  }
}

}

上机练习4 验证用户登入信息
package tz1;

import java.util.Scanner;
/*
* 上机练习4 验证用户登入信息
*/
public class dome2 {
public static void main(String[] args) {
  String name ;//定义用户名
  String password ;//定义用户密码
  int fas = 3;//定义输错的次数

  Scanner input = new Scanner(System.in);
  for (int i = 1; i <= 3; i++) {
   System.out.println("请输入用户名:");
   name = input.next();

   System.out.println("请输入密码：");
   password = input.next();

   if (name.equals("jim") || password.equals("123456")) {
    System.out.println("欢迎登入系统");
    break;
   }
   if (i == 3) {

    System.out.println("对不起，您3次都输入错误");
    break;
   } else {
    System.out.println("输入错误！您还有" + (fas - i) + "机会");

    continue;
   }
  }
}

}
简答题
1计算周一到周五的平均学习时间
package com.bdqn.dome;
import java.util.Scanner;
public class dome8 {
public static void main(String[] args) {
  Scanner input = new Scanner(System.in);

  double total=0;
  for (int i = 0; i < 5; i++) {
   System.out.println("请输入周"+(i+1)+"的学习时间：");
   double time = input.nextDouble();
   total += time;
  }
  System.out.println("周一到周五平均学习时间是"+total/5.0+"小时");
}

}
2求鸡和兔子数量
package com.bdqn.dome;

public class dome9 {
public static void main(String[] args) {
  int chookNum, rabitNum;
  for (chookNum = 0; chookNum < 35; chookNum++) {
   // 鸡等于0 鸡小于35 鸡的数量加1
   // 兔子的数量等于35减去鸡的数量
   rabitNum = 35 - chookNum;
   if (2 * chookNum + 4 * rabitNum == 94) {

System.out.println("鸡有" + chookNum + "只，免有" + rabitNum + "只");
}

}

}
}
3.FlipFlop游戏
package com.bdqn.dome;

//开发一个标题为"flipfoip"的游戏
public class dome10 {
public static void main(String[] args) {
  for (int i = 1; i <= 100; i++) {
   if (i % 3 == 0 && i % 5 == 0) {// 如果能被3整除并且能被5整除
    System.out.println("flipfoip");// 就输出flipfoip
   } else if (i % 5 == 0) {
    System.out.println("foip");
   } else if (i % 3 == 0) {
    System.out.println("flip");
   } else {
    System.out.println(i);
   }
  }
}

}
4.男人，女人，小孩的数量。
package com.bdqn.dome;

public class dome11 {
public static void main(String[] args) {
  int man, women, kids;
  for (kids = 1; kids <= 50; kids++) {
   for (women = 1; women < 25; women++) {
    for (man = 1; man < 16; man++) {
     if (3 * man + 2 * women + kids == 50) {
      if (man + women + kids == 30) {
      }
      System.out.println("男人有" + man + "女人有" + women + "小孩有" + kids);
     }

    }
   }
  }
}

}