java第六次作业
1.使用for循环计算1-100的和,除了以3结尾的那些数
package DaySeven; public class Test1 { public static void main(String[] args) { int sum = 0; for (int i = 0; i < 100; i++) { int ge = i % 10; if (ge != 3) { sum += i; } } System.out.println(sum); } }
2.使用二重循环输出以下图形
*
***
*****
*******
*****
****
***
**
*
package DaySeven; public class Test2 { public static void main(String[] args) { for (int i = 0; i <= 7; i=i+2) { for (int k = 0; k<=(7-i)/2; k++) { System.out.print(" "); } for (int j = 0; j <=i; j++) { System.out.print("*"); } System.out.println(); } } }
package DaySeven; public class Test3 { public static void main(String[] args) { for (int i = 6; i >0; i--) { for (int j = i; j >0; j--) { System.out.print("*"); } System.out.println(); } } }
3.循环输入学生姓名,直到输入‘Q’程序结束。
package DaySeven; import java.util.Scanner; public class Test4 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); while (true) { System.out.println("输入学生姓名"); String name = sc.next(); System.out.println(name); if (name.equals("Q")) break; } } }
4.输入5个学生成绩,求和,当输入不合法的时候,提示输入错误重新输入。
package DaySeven; import java.util.Scanner; public class Test5 { public static void main(String[] args) { System.out.println("输入学生成绩"); double sum = 0; Scanner sc = new Scanner(System.in); for (int i = 0; i < 5; i++) { double score = sc.nextDouble(); if (score < 0 || score > 100) { System.out.println("输入的成绩不合法重新输入"); double score1 = sc.nextDouble(); score = score1; } sum = sum+score; } System.out.println(sum); } }
5.计算 1+ 1/(1+2)+ 1/(1+2+3)+ 1/(1+2+3+4) +…………+1/(1+2+....+10)
package DaySeven; public class Test6 { public static void main(String[] args) { double sum = 0.0; int sum1 = 0; for (int i = 1; i <=10; i++) { sum1 +=i; sum += 1.0/sum1; } System.out.println(sum); } }
作业
1.产生一个1-99的随机数,猜数字,若大了就提示“大了点”,若小了就提示“小了点”直到猜对为止。
(判断猜的次数,如果1-3次,提示太棒了 如果5-8次 一般般 如果8次以上 太笨了)
package homework; import java.util.Random; import java.util.Scanner; public class test27 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); Random r = new Random(); int num = r.nextInt(100) + 1; int count = 0; for (int i = 1; i <= 100; i++) { System.out.println("输入你想的数字"); int a = sc.nextInt(); if (a > num) { System.out.println("大了点"); } else if (a < num) { System.out.println("小了点"); } else { System.out.println("幸运数字:" + num); System.out.println("猜对了"); break; } count += 1; } System.out.println("累计次数" + count); if (count>= 1 && count <= 3) { System.out.println("太棒了"); } else if (count > 3 && count <= 8) { System.out.println("一般般"); } else if (count > 8) { System.out.println("太笨了"); } } }
2.输入一个数,判断是不是质数(只能被1和自身整除的数是质数)
package homework; import java.util.Scanner; public class tets28 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("输入一个数"); int a = sc.nextInt(); int b; boolean zhishu = true; for (b = 2; b < a - 1; b++) { if (a % b == 0) { zhishu = false; break; } } if (zhishu == true) { System.out.println("是质数"); } else { System.out.println("不是质数"); } } }
3.求裴波那契数列的第20项是什么。裴波那契数列,1,1,2,3,5,8,13,21……
package homework; public class test29 { public static void main(String[] args) { int a = 1; int b = 1; int c = 0; for (int i = 3; i < 21; i++) { c = a + b; a = b; b = c; } System.out.println("第20项:" + c); } }
posted on 2021-04-12 21:08 chenyulin11 阅读(23) 评论(0) 编辑 收藏 举报