import java.util.*;
class StudentKey implements Comparable {
	double d=0;
	String s="";
	StudentKey (double d) {
		this.d=d;
	}
	StudentKey (String s) {
		this.s=s;
	}
	public int compareTo(Object b) {
		StudentKey st=(StudentKey)b;
		if((this.d-st.d)==0)
			return -1;
		else
			return (int)((this.d-st.d)*1000);
	}
}
class StudentIF {
	String name=null;
	int ID=0;
	double math,english,computer,total,aver;
	StudentIF(String s, double m, double e, double f, double a,double b,int c) {
		name=s;
		math=m;
		english=e;
		computer=f;
		total=a;
		aver=b;
		ID=c;
	}
}
public class Student {
	public static void main(String args[]) {
		TreeMap<StudentKey, StudentIF> treemap = new TreeMap<StudentKey, StudentIF>();
		String str[] = {"其米仁增","李梓豪", "贾海粟", "夏云霄", "贾普涵"};
		int ID[] ={20165239,20165201,20165202,20165203,20165204};
		double math[] = {96, 77, 63, 89, 96};
		double english[] = {87, 70, 68, 86, 92};
		double computer[] = {97, 66, 73, 66, 91};
		double total[] = new double[5];
		double aver[] = new double[5];
		StudentIF student1[] = new StudentIF[5];
		StudentIF student2[] = new StudentIF[5];
		for (int k = 0; k < student1.length; k++) {
			total[k] = math[k] + english[k] + computer[k];
			aver[k] = total[k] / 3;
		}
		for (int k = 0; k < student1.length; k++) {
			student1[k] = new StudentIF(str[k], math[k], english[k], computer[k], total[k], aver[k], ID[k]);
		}
		StudentKey key[] = new StudentKey[5];
		student2= student1;
		for (int k = 0; k < key.length; k++) {
			key[k] = new StudentKey(student1[k].ID);
		}
		for (int k = 0; k < student1.length; k++) {
			treemap.put(key[k], student1[k]);
		}
		for (int k = 0; k < key.length; k++) {
			key[k] = new StudentKey(student1[k].total);
		}
		for (int k = 0; k < student1.length; k++) {
			treemap.put(key[k], student1[k]);
		}
		int number = treemap.size();
		System.out.println("学生共有" + number + "个,按总成绩排序:");
		Collection<StudentIF> collection = treemap.values();
		Iterator<StudentIF> iter = collection.iterator();
		int i=0;
		while (iter.hasNext()) {
			StudentIF stu = iter.next();
			System.out.println(" 学号 " + stu.ID + " 姓名 " + stu.name + " 总成绩 " + stu.total);
			i++;
			if(i==5)
				System.out.println("学生共有" + number + "个,按学号排序:");
		}
	}
}