Comparable Implementation in Java: Explanation & Practice

Problem summary

Create a Student class that implements Comparable to sort by grade.

Starter code

import java.util.*;

// Student implements Comparable<Student>
// compareTo() based on grade (higher first)

public class Main {
    public static void main(String[] args) {
        // Create list, sort, print top student
    }
}

Expected output and test cases

• Highest grade first

  Top student: Alice (95)

• Different top

  Top student: Bob (88)

• Perfect score

  Top student: Carol (100)

Hints

1. compareTo returns negative, zero, or positive
2. For descending: other.grade - this.grade
3. Collections.sort() uses compareTo

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