Add SquareFreeInteger to maths

Author: iamcodinghere22

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

@@ -0,0 +1,38 @@
+public final class SquareFreeInteger{
+
+/**
+ * A square-free integer is an integer divisible by no perfect square other than 1 
+ * In other words, its prime factorization has no repeated factors.
+ * Examples: 1, 2, 3, 5, 6, 7, 10, 11, 13, 14, 15...
+ * Non-examples: 4, 8, 9, 12, 16, 18 (all divisible by 4 or 9)
+ * 
+ * @see <a href="https://en.wikipedia.org/wiki/Square-free_integer">Square-free integer (Wikipedia)</a>
+ */
+
+    private SquareFreeInteger(){
+
+    }
+
+    /**
+     * Checks if a given number is square-free.
+     * 
+     * @param num the number to check(this must be positive)
+     * @return true if num is square-free , false otherwise
+     * @throws IllegalArgumentException if num is not positive
+     * 
+     */
+    public static boolean isSquareFree(int num){
+        if(num<=0){
+            throw new IllegalArgumentException("Input must be a positive integer.");
+        }
+
+        for(int i=2; (long)i*i<=num ;i++){
+            if(num%(i*i)==0){
+                return false;
+            }
+        }
+        return true;
+
+        
+    }
+}

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

@@ -0,0 +1,34 @@
+package com.thealgorithms.maths;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+class SquareFreeIntegerTest {
+
+    @Test
+    void testSquareFreeNumbers() {
+        assertTrue(SquareFreeInteger.isSquareFree(1));
+        assertTrue(SquareFreeInteger.isSquareFree(2));
+        assertTrue(SquareFreeInteger.isSquareFree(3));
+        assertTrue(SquareFreeInteger.isSquareFree(6));
+        assertTrue(SquareFreeInteger.isSquareFree(15));
+    }
+
+    @Test
+    void testNonSquareFreeNumbers() {
+        assertFalse(SquareFreeInteger.isSquareFree(4));
+        assertFalse(SquareFreeInteger.isSquareFree(8));
+        assertFalse(SquareFreeInteger.isSquareFree(9));
+        assertFalse(SquareFreeInteger.isSquareFree(12));
+        assertFalse(SquareFreeInteger.isSquareFree(18));
+    }
+
+    @Test
+    void testInvalidInput() {
+        assertThrows(IllegalArgumentException.class, () -> SquareFreeInteger.isSquareFree(0));
+        assertThrows(IllegalArgumentException.class, () -> SquareFreeInteger.isSquareFree(-5));
+    }
+}