Putting the basics together

1 Learn

Real programs mix everything: variables hold data, arrays hold lists, loops repeat, if decides, and methods keep it tidy.

Today's example finds the class topper and average using all of these together.

2 See the Code

Java

public class ClassReport {
    static double average(int[] m) {
        int total = 0;
        for (int x : m) total += x;
        return (double) total / m.length;
    }

    public static void main(String[] args) {
        String[] names = {"Ananya", "Ravi", "Meena"};
        int[] marks = {81, 93, 76};
        int best = 0;
        for (int i = 1; i < marks.length; i++) {
            if (marks[i] > marks[best]) best = i;
        }
        System.out.println("Topper: " + names[best]);
        System.out.println("Average: " + average(marks));
    }
}

Two arrays share positions: names[i] goes with marks[i].
The loop remembers the index of the highest mark.
(double) total converts to decimal so the average keeps its fraction.

Output

Topper: Ravi
Average: 83.33333333333333

3 Practice

Add a method countPassed(int[] m) that returns how many marks are 35 or more.

Try it in your own Java setup or write it in the Practice Notebook.

4 Quick Check

1. Why do we write (double) total?
2. Which concept keeps the average code reusable?

Step 5

Answer and check the Quick Check above to unlock this.

Day 12