- 数组的声明与使用
| package works2022.Week9; |
| |
| import java.util.Scanner; |
| |
| public class Task60 { |
| public static void main(String []args) |
| { |
| System.out.println("Please enter the number:"); |
| Scanner in = new Scanner(System.in); |
| int []stat=new int[10]; |
| while(in.hasNext()) |
| { |
| int a=in.nextInt(); |
| if(a<1||a>100) |
| { |
| System.out.println("The number "+a+" not in a right range."); |
| }else stat[a/10]=stat[a/10]+1; |
| } |
| for(int i=0;i<10;i++){ |
| System.out.format("%02d to %02d \t",(i*10+1),((i+1)*10)); |
| for(int j=0;j<stat[i];j++) |
| { |
| System.out.print("*"); |
| } |
| System.out.println("("+stat[i]+")"); |
| } |
| in.close(); |
| } |
| } |
| |
| package works2022.Week9; |
| |
| import java.util.Scanner; |
| |
| public class Task61 { |
| public static void main(String [] args) |
| { |
| String equivalences [] = {"", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", |
| "eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", |
| "seventeen", "eighteen", "nineteen", "twenty", "twenty one", |
| "twenty two", "twenty three", "twenty four", "twenty five", "twenty six", |
| "twenty seven", "twenty eight", "twenty nine"}; |
| Scanner in = new Scanner(System.in); |
| int hour=0,minute=0; |
| System.out.println("Please enter the hour:"); |
| while(in.hasNext()) |
| { |
| hour=in.nextInt(); |
| if(hour>=1&&hour<=12) |
| { |
| break; |
| }else{ |
| System.out.println("The number you enter is not right, please enter a new number:"); |
| } |
| } |
| System.out.println("Please enter the minute:"); |
| while(in.hasNext()) |
| { |
| minute=in.nextInt(); |
| if(minute>=0&&minute<=59) |
| { |
| break; |
| }else{ |
| System.out.println("The number you enter is not right, please enter a new number:"); |
| } |
| } |
| if(minute%15==0) |
| { |
| switch(minute/15) |
| { |
| case 1:System.out.println("quarter past "+equivalences[hour]);break; |
| case 2:System.out.println("half past "+equivalences[hour]);break; |
| case 3:System.out.println("quarter to "+equivalences[hour+1]);break; |
| } |
| }else if(minute>30) |
| { |
| System.out.println(equivalences[60-minute]+" minute(s) to "+equivalences[hour+1]); |
| }else if(minute==0) |
| { |
| System.out.println(equivalences[hour]+"o'clock"); |
| }else{ |
| System.out.println(equivalences[minute]+" minute(s) pass to "+equivalences[hour]); |
| } |
| in.close(); |
| } |
| } |
| |
| package works2022.Week9; |
| import java.util.Scanner; |
| public class Task62 { |
| |
| private boolean validateDate(int year,int month,int day) |
| { |
| if(month<1||month>12) return false; |
| int []m={0,31,28,31,30,31,30,31,31,30,31,30,31}; |
| if(month==2&&(year%4==0)&&(year%100==0)||(year%400==0)) |
| { |
| if(day>29) return false; |
| else return true; |
| }else{ |
| if(day>m[month]) return false; |
| else return true; |
| } |
| } |
| public static void main(String []args) |
| { |
| Scanner in = new Scanner(System.in); |
| Task62 t=new Task62(); |
| int year=0,month=0,day=0; |
| System.out.println("Please enter the year:"); |
| year=in.nextInt(); |
| System.out.println("Please enter the month:"); |
| month=in.nextInt(); |
| System.out.println("Please enter the day:"); |
| day=in.nextInt(); |
| if(t.validateDate(year,month,day)) System.out.println("It is a right date."); |
| else System.out.println("It is not a right date."); |
| in.close(); |
| } |
| } |
| |
| package works2022.Week9; |
| |
| import java.util.Scanner; |
| |
| public class Task63 { |
| |
| public static boolean luhnFormula(int a[],int n) |
| { |
| int tot1=0,tot2=0; |
| int temp=0; |
| if(n==13&&a[0]!=4) return false; |
| for(int i=0;i<n;i=i+2) |
| { |
| temp=a[i]*2; |
| while(temp!=0) |
| { |
| tot1=tot1+temp%10; |
| temp=temp/10; |
| } |
| } |
| for(int i=1;i<n;i=i+2) |
| { |
| tot2+=a[i]; |
| } |
| int ans=tot1+tot2; |
| if(ans%10==0) |
| { |
| return true; |
| }return false; |
| } |
| public static void main(String []args) |
| { |
| int []a=new int[16]; |
| Scanner in=new Scanner(System.in); |
| String num_s; |
| num_s=in.nextLine(); |
| for(int i=0;i<num_s.length();i++) |
| { |
| a[i]=num_s.charAt(i)-'0'; |
| } |
| if(luhnFormula(a,num_s.length())) |
| { |
| System.out.println("The credit card number is true."); |
| }else System.out.println("The credit card number is false."); |
| in.close(); |
| } |
| } |
| |