Java Code Example: nested for loop

This code is written in Java and defines a class called NestedLoop. It contains a single main method that performs two nested for loops and counts the number of times each loop runs.

The outer for loop (for (int i = 20; i > a; i--)) starts from i = 20 and decrements i by 1 until it becomes less than or equal to a. The inner for loop (for (int j = 0; j < b; j++)) starts from j = 0 and increments j by 1 until it becomes less than b.

The two counters c1 and c2 keep track of the number of times each loop runs. The inner loop increments the value of c2 by 1 each time it runs. The outer loop increments the value of c1 by 1 each time it completes. The condition if (i == j) checks if the current value of i is equal to the current value of j. If this condition is true, the program prints a message indicating the number of times each loop has run, along with the calculation of the total number of times the inner loop runs (c1 * b).

class NestedLoop {
    public static void main(String[] args) {
        int a = 5, b = 7, c1 = 0, c2 = 0;

        for (int i = 20; i > a; i--) {
            c1++;
            for (int j = 0; j < b; j++) {
                c2++;
                if (i == j) {
                    System.out.println("How many times the loops are run?");
                    System.out.print("first loop: " + c1 + "\nsecond loop: " 
                            + c2 + " (" + c1 + " * " + b + ")");
                }
            }
        }
    }
}

Output

How many times the loops are run?
first loop: 15
second loop: 105 (15 * 7)