Problem Description
设计一个学生添加和查询的系统,从键盘读入学生的数据,然后再从屏幕显示出来。
Input
第一行有2个整数N和M,其中:N——学生数量,M——学生属性数量;
第二行有M个字符串,表示学生的属性名称,其中第1个属性id表示关键字;其中各字段属性的数据类型是确定的。
接下来有N行M列数据,分别表示学生各种属性的值,关键字相同的记录代表一个学生(后来读入的信息覆盖前面读入数据)
Output
输出所有学生的属性及数据。(每行的列数据之间用‘\t’进行分隔)
Sample Input
5 4 id name birthday score 0001 Mike 1990-05-20 98.5 0002 John 1992-05-20 67 0003 Hill 1994-05-02 36.5 0004 Christ 1996-05-20 86.5 0001 Jack 1998-05-20 96
Sample Output
id:0001 name:Jack birthday:1998_5_20 score:96.0 id:0002 name:John birthday:1992_5_20 score:67.0 id:0003 name:Hill birthday:1994_5_2 score:36.5 id:0004 name:Christ birthday:1996_5_20 score:86.5
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
class Student {
String id, name, date;
double score;
public Student(String id, String name, String date, double score) {
super();
this.id = id;
this.name = name;
this.date = date;
this.score = score;
}
String dateConvert(String date) throws ParseException {
SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd");
SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy_M_d");
Date date1 = sdf1.parse(date);
return sdf2.format(date1);
}
@Override
public String toString() {
String str = null;
try {
str = "id:" + id + "\tname:" + name + "\tbirthday:" + dateConvert(date) + "\tscore:"
+ String.format("%.1f", score);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return str;
}
}
public class Mainn {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
int n = s.nextInt();
Map<String, Student> map = new HashMap<String, Student>();
s.nextLine();
s.nextLine();
for (int i = 1; i <= n; i++) {
Student stu = new Student(s.next(), s.next(), s.next(), s.nextDouble());
map.put(stu.id, stu);
}
Set<String> keySet = map.keySet();
List<String> list = new ArrayList<String>(keySet);
Collections.sort(list);
for (String id : list) {
Student student = map.get(id);
System.out.println(student);
}
s.close();
}
}