From 63eb39b2f38a831d92497f724b658f010e71997a Mon Sep 17 00:00:00 2001
From: Sumanth Desai <sumanthdesaiiiii@gmail.com>
Date: Thu, 19 Feb 2026 15:15:20 +0530
Subject: [PATCH] Add NeonNumber algorithm in maths package

---
 .../com/thealgorithms/maths/NeonNumber.java   | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 src/main/java/com/thealgorithms/maths/NeonNumber.java

diff --git a/src/main/java/com/thealgorithms/maths/NeonNumber.java b/src/main/java/com/thealgorithms/maths/NeonNumber.java
new file mode 100644
index 000000000000..aa09817e6b27
--- /dev/null
+++ b/src/main/java/com/thealgorithms/maths/NeonNumber.java
@@ -0,0 +1,39 @@
+package com.thealgorithms.maths;
+
+/**
+ * This class checks whether a number is a Neon Number.
+ * A Neon number is a number where the sum of digits of
+ * its square is equal to the number itself.
+ *
+ * Example:
+ * 9^2 = 81 → 8 + 1 = 9 (Neon Number)
+ */
+public final class NeonNumber {
+
+    private NeonNumber() {
+        // Prevent instantiation
+    }
+
+    /**
+     * Checks if a number is a Neon Number.
+     *
+     * @param number the input number
+     * @return true if the number is a Neon Number, otherwise false
+     * @throws IllegalArgumentException if the number is negative
+     */
+    public static boolean isNeon(int number) {
+        if (number < 0) {
+            throw new IllegalArgumentException("Number must be non-negative");
+        }
+
+        int square = number * number;
+        int sum = 0;
+
+        while (square > 0) {
+            sum += square % 10;
+            square /= 10;
+        }
+
+        return sum == number;
+    }
+}