1. Introduction

In this tutorial, we will create a Java program to count the number of digits in an integer. This is a fundamental concept that can be useful in various applications such as data validation, arithmetic operations, and data analysis.

2. Program Steps

1. Define a class named CountDigits.

2. In the main method, declare and initialize an integer whose digits you want to count.

3. Create a variable count initialized to 0, which will store the number of digits.

4. Use a while loop to iterate through each digit of the number, incrementing count until the number becomes 0.

5. Print the value of count which will be the number of digits in the given integer.

3. Code Program

public class CountDigits { // Step 1: Define a class named CountDigits

    public static void main(String[] args) { // Main method

        // Step 2: Declare and initialize an integer
        int number = 123456;

        // Step 3: Initialize count to 0
        int count = 0;

        // Step 4: Use a while loop to count the digits
        while (number != 0) {
            number /= 10; // remove the last digit
            count++; // increment count
        }

        // Step 5: Print the count
        System.out.println("Number of digits: " + count);
    }
}

Output:

Number of digits: 6

4. Step By Step Explanation

– Step 1: A class named CountDigits is defined.

– Step 2: An integer variable number is declared and initialized with a value whose digits we want to count.

– Step 3: A variable count is initialized to 0. This will hold the number of digits.

– Step 4: A while loop is used to iterate through each digit of the number. In each iteration, the last digit is removed by dividing the number by 10, and count is incremented.

– Step 5: The program prints the value of count, which is the number of digits in the original number.