Java编程题每日一练day1

Day1共7题

package com.pcx.day1; /** * 设一个字符数组，对其元音字母进行统计 * a e i o u * @author Administrator * */ public class YuanYin {     public static void main(String[] args) {         char [] chars={'a','b','c','d','e'};         int count=0;         for (int i = 0; i < chars.length; i++) {             if (chars[i]=='a'||chars[i]=='e'||chars[i]=='i'||chars[i]=='o'||chars[i]=='u') {                 count++;             }         }         System.out.println("元音字母的个数为："+count);     } }

package com.pcx.day1; /** * 打印1000以内的水仙花数 * 153 * @author Administrator * */ public class ShuiXianHua {     public static boolean isShuiXianHuan(int a){         int ge=a%10;         int shi=a/10%10;         int bai=a/100;         if (Math.pow(ge,3)+Math.pow(shi,3)+Math.pow(bai,3)==a) {             return true;         }else {             return false;         }     }          public static void main(String[] args) {         for (int i = 100; i < 1000; i++) {             if (isShuiXianHuan(i)) {                 System.out.println(i+" 是水仙花数");             }         }     } }

package com.pcx.day1;   import java.util.Calendar;   public class RiQi {     /**      * 接收三个参数分别是年，月，日,然后返加一个Calendar类型的对象      */     public static Calendar getCalendar(int year, int month, int day){         Calendar c=Calendar.getInstance();         c.set(year, month, day);         return c;     }          /**      * 打印此日期是一个月的第几天，一年的第几天，一周的第几天，此天是周几，这个月的第一天是周几，是一周的第几天。      * @param c      */     public static void show(Calendar c ){         System.out.println("这个月的第几天："+c.get(Calendar.DAY_OF_MONTH));         System.out.println("这个年的第几天："+c.get(Calendar.DAY_OF_YEAR));         System.out.println("这个周的第几天："+c.get(Calendar.DAY_OF_WEEK));         System.out.println("这天周几："+(c.get(Calendar.DAY_OF_WEEK)-1));                  c.set(Calendar.DATE, 1);         System.out.println("这个月的第一天是一周的第几天："+c.get(Calendar.DAY_OF_WEEK));         System.out.println("这天周几："+(c.get(Calendar.DAY_OF_WEEK)-1));     }          public static void main(String[] args) {         show(getCalendar(2015, 6, 28));     } }

package com.pcx.day1;   public class Person {     private String name;     private int age ;     private boolean gendar;//true 男 false 女     public String getName() {         return name;     }     public void setName(String name) {         this.name = name;     }     public int getAge() {         return age;     }     public void setAge(int age) {         this.age = age;     }     public boolean isGendar() {         return gendar;     }     public void setGendar(boolean gendar) {         this.gendar = gendar;     }          public void walk(){         System.out.println(this.name+"在走。。。");     }          public void eat(){         System.out.println(this.name+"在吃。。。");     } }   package com.pcx.day1;   public class PersonTest {     public static void main(String[] args) {         //Lucy，女，23岁；Jame，男，25岁         Person p1=new Person();         p1.setName("lucy");         p1.setGendar(false);         p1.setAge(23);         Person p2=new Person();         p2.setName("Jame");         p2.setGendar(true);         p2.setAge(25);         p1.walk();         p1.eat();         p2.walk();         p2.eat();     } }

package com.pcx.day1; /** * 求1+2!+3!+...+20!的和 * @author Administrator * */ public class Jiechenghe {     public static int getJieCheng(int a){         if(a==0||a==1){             return 1;         }else {             return a*getJieCheng(a-1);         }     }     public static void main(String[] args) {         int sum=0;         for (int i = 1; i <=20; i++) {             sum+=getJieCheng(i);         }         System.out.println("1+2!+3!+...+20!="+sum);     } }

package com.pcx.day1; /** * 一球从100米高度自由落下，每次落地后反跳回原高度的一半； * 再落下，求它在 第10次落地时，共经过多少米？第10次反弹多高？ * @author Administrator * */ public class Qiu {     public static void main(String[] args) {         int gao=100,gn=gao/2;         int total=0+100;         for (int i =2; i <=10; i++) {             total=total+2*gn;             gn=gn/2;         }         System.out.println("十次一共经过了："+total+"米");         System.out.println("第十次反弹："+gn);     } }