《Java 基础编程练习题》由会员分享，可在线阅读，更多相关《Java 基础编程练习题（30页珍藏版）》请在金锄头文库上搜索。
1、Java 基础编程练习题1、编写程序实现对给定的 4 个整数从大到小的顺序排列。package HomeWork01;import java.util.Scanner;public class HomeWork01 static int number=4; /输入4个数存放在数组中 static int t1 = new intnumber; public static void main(String args) HomeWork01 jiejie=new HomeWork01(); jiejie.shunxun(); void shunxun() System.out.println(请输
2、入4个数：); Scanner in_t1 = new Scanner(System.in);/循环输入数组 for(int i=0;inumber;i+) t1i=in_t1.nextInt(); for (int i = 0; i t1.length; i+) int pos = i; for (int j = i + 1; j t1j) pos = j; if (pos != i) t1i = t1i + t1pos; t1pos = t1i - t1pos; t1i = t1i - t1pos; for (int i = t1.length - 1; i = 0; i-) System
3、.out.print(t1i + t); 2、编写程序求一元二次方程的根。package HomeWork02;import java.util.Scanner;public class HomeWork02/=b2-4ac的值,若小于0,一元二次方程无根.若等于0,一元二次方程有两个相等的根.若大于0,一元二次方程有两个不相等的实数根 public static void main(String args) Scanner sc = new Scanner(System.in); System.out.println(输入2次方的系数); int a = sc.nextInt(); Syst
4、em.out.println(输入1次方的系数); int b = sc.nextInt(); System.out.println(输入0次方的系数); int c = sc.nextInt(); if(b*b - 4*a*c)=97&zimu=122) /判断是否是小写字母 System.err.println(该字母是小写字母); zimu=(char) (zimu-32); /如果是小写字母则 将其转换成大写字母 System.err.println(转换之后的大写字母是：+zimu); else System.out.println(该字母不是小写字母！); 4、输入 3 个正数，判
5、断能否构成一个三角形。package HomeWork04;import java.util.Scanner;public class HomeWork04 public static void main(String args) int a; int b; int c; System.out.println(请输入三个正整数：); Scanner in=new Scanner(System.in); a=in.nextInt(); b=in.nextInt(); c=in.nextInt(); if(a=0|b=0|cc&(a+c)b&(b+c)a) System.out.println(能
6、构成三角形！); else System.out.println(不能构成三角形！); 5、编写程序，对输入的年、月、日，给出该天是该年的第多少天？package HomeWork05;import java.util.Scanner;public class HomeWork05 public static void main(Stringargs) Scanner sc =new Scanner(System.in); System.out.print(年); int year=sc.nextInt(); System.out.print(月); int month=sc.nextInt(
7、); System.out.print(日); int day=sc.nextInt(); int days=0; switch(month) case 12:days+=30; case 11:days+=31; case 10:days+=30; case 9:days+=31; case 8:days+=31; case 7:days+=30; case 6:days+=31; case 5:days+=30; case 4:days+=31; case 3: if(year%4=0&year%100!=0)|(year%400=0) days+=29; else days+=28; c
8、ase 2:days+=31; case 1:days+=day; System.out.print(第 + days + 天);6、编写程序，从键盘输入一个 099999 之间的任意数，判断输入的数是几位数？package HomeWork06;import java.util.Scanner;public class HomeWork06 public static void main(Stringargs) Scanner sc =new Scanner(System.in); System.out.print(请输入一个099999 之间的任意数); int number=sc.nextInt(); if(number/10000=1&number/10000=1) System.out.println(number+t是4位数); else if(number/100=1) System.out.println(number+t是3位数); else if(number/10=1) System.out.println(number+t是2位数); else if(number/1=1) System.out.println(number+t是1位数); 7、编写程序，给定一个学生成绩，给出相应等级：90100 优秀8089 良好7079 中等
