HackerRank Inheritance | JS Solution

Problem

HackerRank detailed problem description can be found here.

Sample Input

Robot Bobert 5135617
2
100 80

Sample Output

Name: Bobert, Robot
ID: 5135617
Grade: O

JavaScript Solution

class Student extends Person {
  /*    
  *   Class Constructor
  *   
  *   @param firstName - A string denoting the Person's first name.
  *   @param lastName - A string denoting the Person's last name.
  *   @param id - An integer denoting the Person's ID number.
  *   @param scores - An array of integers denoting the Person's test scores.
  */
  constructor(firstName, lastName, idNumber, scores) {
    super(firstName, lastName, idNumber);
    this.scores = scores;
  }

  /*    
  *   Method Name: calculate
  *   @return A character denoting the grade.
  */
  // Solution #1
  calculate() {
    const averageScore = this.scores.reduce((a, b) => a + b) / this.scores.length;

    if (averageScore >= 90 && averageScore <= 100) {
      return 'O';
    } else if (averageScore >= 80 && averageScore < 90) {
      return 'E';
    } else if (averageScore >= 70 && averageScore < 80) {
      return 'A';
    } else if (averageScore >= 55 && averageScore < 70) {
      return 'P';
    } else if (averageScore >= 40 && averageScore < 55) {
      return 'D';
    } else {
      return 'T';
    }
  }
    
  // Solution #2
  calculate() {
    const averageScore = this.scores.reduce((a, b) => a + b) / this.scores.length;

    switch (true) {
      case (averageScore >= 90 && averageScore <= 100):
        return 'O';
      case (averageScore >= 80 && averageScore < 90):
        return 'E';
      case (averageScore >= 70 && averageScore < 80):
        return 'A';
      case (averageScore >= 55 && averageScore < 70):
        return 'P';
      case (averageScore >= 40 && averageScore < 55):
        return 'D';
      default:
        return 'T';
    }
  }
}

Resources

1. Inheritance algorithm by HackerRank
2. Classes and switch by MDN Web Docs