Format code and add Wikipedia URL for Lagrange's theorem

Author: BEASTSHRIRAM

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

@@ -3,37 +3,50 @@
 /**
  * Implementation of Lagrange's Four Square Theorem
  * Find minimum number of perfect squares that sum to given number
+ *
+ * @see <a href="https://en.wikipedia.org/wiki/Lagrange%27s_four-square_theorem">Lagrange's Four Square Theorem</a>
  * @author BEASTSHRIRAM
  */
 public final class SumOfSquares {
-    
+
     private SumOfSquares() {
         // Utility class
     }
-    
+
     /**
      * Find minimum number of perfect squares that sum to n
+     *
      * @param n the target number
      * @return minimum number of squares needed
      */
     public static int minSquares(int n) {
-        if (isPerfectSquare(n)) return 1;
-        
+        if (isPerfectSquare(n)) {
+            return 1;
+        }
+
         for (int i = 1; i * i <= n; i++) {
             int remaining = n - i * i;
-            if (isPerfectSquare(remaining)) return 2;
+            if (isPerfectSquare(remaining)) {
+                return 2;
+            }
         }
-        
+
         // Legendre's three-square theorem
         int temp = n;
-        while (temp % 4 == 0) temp /= 4;
-        if (temp % 8 == 7) return 4;
-        
+        while (temp % 4 == 0) {
+            temp /= 4;
+        }
+        if (temp % 8 == 7) {
+            return 4;
+        }
+
         return 3;
     }
-    
+
     private static boolean isPerfectSquare(int n) {
-        if (n < 0) return false;
+        if (n < 0) {
+            return false;
+        }
         int root = (int) Math.sqrt(n);
         return root * root == n;
     }

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

@@ -1,66 +1,68 @@
 package com.thealgorithms.maths;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import org.junit.jupiter.api.Test;
 
 /**
  * Test class for SumOfSquares
+ *
  * @author BEASTSHRIRAM
  */
 class SumOfSquaresTest {
 
     @Test
     void testPerfectSquares() {
         // Perfect squares should return 1
-        assertEquals(1, SumOfSquares.minSquares(1));   // 1^2
-        assertEquals(1, SumOfSquares.minSquares(4));   // 2^2
-        assertEquals(1, SumOfSquares.minSquares(9));   // 3^2
-        assertEquals(1, SumOfSquares.minSquares(16));  // 4^2
-        assertEquals(1, SumOfSquares.minSquares(25));  // 5^2
+        assertEquals(1, SumOfSquares.minSquares(1)); // 1^2
+        assertEquals(1, SumOfSquares.minSquares(4)); // 2^2
+        assertEquals(1, SumOfSquares.minSquares(9)); // 3^2
+        assertEquals(1, SumOfSquares.minSquares(16)); // 4^2
+        assertEquals(1, SumOfSquares.minSquares(25)); // 5^2
     }
 
     @Test
     void testTwoSquares() {
         // Numbers that can be expressed as sum of two squares
-        assertEquals(2, SumOfSquares.minSquares(2));   // 1^2 + 1^2
-        assertEquals(2, SumOfSquares.minSquares(5));   // 1^2 + 2^2
-        assertEquals(2, SumOfSquares.minSquares(8));   // 2^2 + 2^2
-        assertEquals(2, SumOfSquares.minSquares(10));  // 1^2 + 3^2
-        assertEquals(2, SumOfSquares.minSquares(13));  // 2^2 + 3^2
+        assertEquals(2, SumOfSquares.minSquares(2)); // 1^2 + 1^2
+        assertEquals(2, SumOfSquares.minSquares(5)); // 1^2 + 2^2
+        assertEquals(2, SumOfSquares.minSquares(8)); // 2^2 + 2^2
+        assertEquals(2, SumOfSquares.minSquares(10)); // 1^2 + 3^2
+        assertEquals(2, SumOfSquares.minSquares(13)); // 2^2 + 3^2
     }
 
     @Test
     void testThreeSquares() {
         // Numbers that require exactly three squares
-        assertEquals(3, SumOfSquares.minSquares(3));   // 1^2 + 1^2 + 1^2
-        assertEquals(3, SumOfSquares.minSquares(6));   // 1^2 + 1^2 + 2^2
-        assertEquals(3, SumOfSquares.minSquares(11));  // 1^2 + 1^2 + 3^2
-        assertEquals(3, SumOfSquares.minSquares(12));  // 2^2 + 2^2 + 2^2
-        assertEquals(3, SumOfSquares.minSquares(14));  // 1^2 + 2^2 + 3^2
+        assertEquals(3, SumOfSquares.minSquares(3)); // 1^2 + 1^2 + 1^2
+        assertEquals(3, SumOfSquares.minSquares(6)); // 1^2 + 1^2 + 2^2
+        assertEquals(3, SumOfSquares.minSquares(11)); // 1^2 + 1^2 + 3^2
+        assertEquals(3, SumOfSquares.minSquares(12)); // 2^2 + 2^2 + 2^2
+        assertEquals(3, SumOfSquares.minSquares(14)); // 1^2 + 2^2 + 3^2
     }
 
     @Test
     void testFourSquares() {
         // Numbers that require exactly four squares (form 4^a * (8b + 7))
-        assertEquals(4, SumOfSquares.minSquares(7));   // 1^2 + 1^2 + 1^2 + 2^2
-        assertEquals(4, SumOfSquares.minSquares(15));  // 1^2 + 1^2 + 2^2 + 3^2
-        assertEquals(4, SumOfSquares.minSquares(23));  // 1^2 + 1^2 + 3^2 + 3^2
-        assertEquals(4, SumOfSquares.minSquares(28));  // 4 * 7, so needs 4 squares
-        assertEquals(4, SumOfSquares.minSquares(31));  // 1^2 + 2^2 + 3^2 + 3^2
+        assertEquals(4, SumOfSquares.minSquares(7)); // 1^2 + 1^2 + 1^2 + 2^2
+        assertEquals(4, SumOfSquares.minSquares(15)); // 1^2 + 1^2 + 2^2 + 3^2
+        assertEquals(4, SumOfSquares.minSquares(23)); // 1^2 + 1^2 + 3^2 + 3^2
+        assertEquals(4, SumOfSquares.minSquares(28)); // 4 * 7, so needs 4 squares
+        assertEquals(4, SumOfSquares.minSquares(31)); // 1^2 + 2^2 + 3^2 + 3^2
     }
 
     @Test
     void testLargerNumbers() {
         // Test some larger numbers
         assertEquals(1, SumOfSquares.minSquares(100)); // 10^2
-        assertEquals(2, SumOfSquares.minSquares(65));  // 1^2 + 8^2
-        assertEquals(3, SumOfSquares.minSquares(19));  // 1^2 + 3^2 + 3^2
-        assertEquals(4, SumOfSquares.minSquares(60));  // 4 * 15, and 15 = 8*1 + 7
+        assertEquals(2, SumOfSquares.minSquares(65)); // 1^2 + 8^2
+        assertEquals(3, SumOfSquares.minSquares(19)); // 1^2 + 3^2 + 3^2
+        assertEquals(4, SumOfSquares.minSquares(60)); // 4 * 15, and 15 = 8*1 + 7
     }
 
     @Test
     void testEdgeCases() {
         // Test edge case
-        assertEquals(1, SumOfSquares.minSquares(0));   // 0^2
+        assertEquals(1, SumOfSquares.minSquares(0)); // 0^2
     }
 }