Merge pull request #179 from Sbiswas001/main

Create ArmstrongNumber.java

Basics/ArmstrongNumber.java

@@ -0,0 +1,79 @@
+package com.sbiswas001.twelveproject;
+
+import java.util.Scanner;
+
+/**
+ * Checks if a number is armstrong or not.
+ * A number is armstrong if the sum of each digit to the power
+ * number of digits is equal to the number itself.
+ * @author Sayan Biswas
+ * @version 25.04.2022
+ */
+public class ArmstrongNumber {
+    /**
+     * Stores the number
+     */
+    private int number;
+
+    /**
+     * Initializes instance variables
+     */
+    private ArmstrongNumber() {
+        number = 0;
+    }
+
+    /**
+     * Inputs a number from user
+     */
+    private void input() {
+        Scanner sc = new Scanner(System.in);
+        System.out.print("Enter number: ");
+        number = Integer.parseInt(sc.nextLine());
+    }
+
+    /**
+     * Returns number of digits of a number
+     * @param n Number to be checked
+     * @return Number of digits
+     */
+    private int numberOfDigits(int n) {
+        return (int)Math.floor(Math.log10(n))+1;
+    }
+
+    /**
+     * Checks if a number is armstrong or not.
+     * A number is armstrong if the sum of each digit to the
+     * power number of digits is equal to the number itself.
+     * @param a Number to be checked
+     * @return true or false
+     */
+    private boolean armstrongCheck(int a) {
+        int sum = 0;
+        while(a > 0) {
+            sum += (int)Math.pow(a % 10,
+                    numberOfDigits(number));
+            a /= 10;
+        }
+        return sum == number;
+    }
+
+    /**
+     * Displays if number is armstrong or not
+     */
+    private void display() {
+
+        System.out.println(armstrongCheck(number) ?
+                "Number is armstrong." :
+                "Number is not armstrong.");
+    }
+
+    /**
+     * Calls other methods
+     * @param args Arguments passed to main method
+     */
+    public static void main(String[] args) {
+        ArmstrongNumber ob = new ArmstrongNumber();
+        ob.input();
+        ob.display();
+    }
+}