HackerRank classes and objects solution in c++ programming

In this HackerRank Classes and Objects problem in c++ programming language A class defines a blueprint for an object. We use the same syntax to declare objects of a class as we use to declare variables of other basic types. For example:

Box box1;          // Declares variable box1 of type Box

Box box2;          // Declare variable box2 of type Box

Kristen is a contender for valedictorian of her high school. She wants to know how many students (if any) have scored higher than her in the 5 exams given during this semester.

Create a class named Student with the following specifications:

1. An instance variable named score to hold a student’s 5 exam scores.
2. A void input() function that reads 5 integers and saves them to scores.
3. An int calculateTotalScore() function that returns the sum of the student’s scores.

HackerRank classes and objects problem solution in c++ programming.

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <cassert>
using namespace std;

// Write your Student class here
class Student {
  private:
    int scores[5];
    int sum;
  public:
    Student() : sum(0) {}
    int calculateTotalScore() {return sum;}
    void input() {
        for(int i=0; i<5; i++) {
            cin >> scores[i];
            sum+=scores[i];
        }
    }
};

int main() {
    int n; // number of students
    cin >> n;
    Student *s = new Student[n]; // an array of n students
    
    for(int i = 0; i < n; i++){
        s[i].input();
    }

    // calculate kristen's score
    int kristen_score = s[0].calculateTotalScore();

    // determine how many students scored higher than kristen
    int count = 0; 
    for(int i = 1; i < n; i++){
        int total = s[i].calculateTotalScore();
        if(total > kristen_score){
            count++;
        }
    }

    // print result
    cout << count;
    
    return 0;
}

Second solution

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <cassert>
using namespace std;

// Write your Student class here
class Student {
    int totalScore = 0;
    public:
    void input() {
        for (int i = 0; i < 5; i++) {
            int x;
            cin >> x;
            totalScore += x;
        }
    }
    int calculateTotalScore() {
        return totalScore;
    }   
};

int main() {
    int n; // number of students
    cin >> n;
    Student *s = new Student[n]; // an array of n students
    
    for(int i = 0; i < n; i++){
        s[i].input();
    }

    // calculate kristen's score
    int kristen_score = s[0].calculateTotalScore();

    // determine how many students scored higher than kristen
    int count = 0; 
    for(int i = 1; i < n; i++){
        int total = s[i].calculateTotalScore();
        if(total > kristen_score){
            count++;
        }
    }

    // print result
    cout << count;
    
    return 0;
}