Made changes to the code to correct the Logic of Armstrong Number (#4619)

* Made changes to the code to correct the Logic of Armstrong Number

* Resolved the issues

* Trying to resolve the Linter error by changing Variable name

* Changed Variable Names : trying to resolve Clang error

src/main/java/com/thealgorithms/maths/Armstrong.java

@@ -1,29 +1,36 @@
 package com.thealgorithms.maths;
 
 /**
- * An Armstrong number is equal to the sum of the cubes of its digits. For
- * example, 370 is an Armstrong number because 3*3*3 + 7*7*7 + 0*0*0 = 370. An
- * Armstrong number is often called Narcissistic number.
+ * This class checks whether a given number is an Armstrong number or not.
+ * An Armstrong number is a number that is equal to the sum of its own digits,
+ * each raised to the power of the number of digits.
  *
- * @author Vivek
+ * For example, 370 is an Armstrong number because 3^3 + 7^3 + 0^3 = 370.
+ * 1634 is an Armstrong number because 1^4 + 6^4 + 3^4 + 4^4 = 1634.
+ * An Armstrong number is often called a Narcissistic number.
+ *
+ * @author satyabarghav
  */
 public class Armstrong {
 
     /**
-     * Checks whether a given number is an armstrong number or not.
+     * Checks whether a given number is an Armstrong number or not.
      *
-     * @param number number to check
-     * @return {@code true} if given number is armstrong number, {@code false}
-     * otherwise
+     * @param number the number to check
+     * @return {@code true} if the given number is an Armstrong number, {@code false} otherwise
      */
     public boolean isArmstrong(int number) {
         long sum = 0;
-        long number2 = number;
-        while (number2 > 0) {
-            long mod = number2 % 10;
-            sum += Math.pow(mod, 3);
-            number2 /= 10;
+        String temp = Integer.toString(number); // Convert the given number to a string
+        int power = temp.length(); // Extract the length of the number (number of digits)
+        long originalNumber = number;
+
+        while (originalNumber > 0) {
+            long digit = originalNumber % 10;
+            sum += Math.pow(digit, power); // The digit raised to the power of the number of digits and added to the sum.
+            originalNumber /= 10;
         }
+
         return sum == number;
     }
 }

src/test/java/com/thealgorithms/maths/ArmstrongTest.java

@@ -5,8 +5,8 @@ import static org.assertj.core.api.Assertions.assertThat;
 import org.junit.jupiter.api.Test;
 
 /**
- * @author Vivek
- * @since 15/03/22
+ * @author satyabarghav
+ * @since 4/10/2023
  */
 class ArmstrongTest {
 
@@ -17,7 +17,9 @@ class ArmstrongTest {
         assertThat(armstrong.isArmstrong(1)).isTrue();
         assertThat(armstrong.isArmstrong(153)).isTrue();
         assertThat(armstrong.isArmstrong(371)).isTrue();
-        assertThat(armstrong.isArmstrong(1634)).isFalse();
+        assertThat(armstrong.isArmstrong(1634)).isTrue();
         assertThat(armstrong.isArmstrong(200)).isFalse();
+        assertThat(armstrong.isArmstrong(548834)).isTrue();
+        assertThat(armstrong.isArmstrong(9474)).isTrue();
     }
 }