add floor

realDuYuanChao · realDuYuanChao · commit 3ae3b2a2dd4a · 2020-10-18T11:22:17.000+08:00
diff --git a/src/main/java/com/examplehub/maths/Floor.java b/src/main/java/com/examplehub/maths/Floor.java
@@ -0,0 +1,7 @@
+package com.examplehub.maths;
+
+public class Floor {
+    public static int floor(double number) {
+        return number - (int) number >= 0 ? (int) number : (int) number - 1;
+    }
+}
diff --git a/src/test/java/com/examplehub/maths/FloorTest.java b/src/test/java/com/examplehub/maths/FloorTest.java
@@ -0,0 +1,19 @@
+package com.examplehub.maths;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class FloorTest {
+    @Test
+    void testFloor() {
+        assertEquals(Math.floor(123.45), Floor.floor(123.45));
+        assertEquals(Math.floor(3.14), Floor.floor(3.14));
+        assertEquals(Math.floor(1), Floor.floor(1));
+        assertEquals(Math.floor(0), Floor.floor(0));
+        assertEquals(Math.floor(-3.14), Floor.floor(-3.14));
+        assertEquals(Math.floor(-3.14), Floor.floor(-3.14));
+        assertEquals(Math.floor(-3), Floor.floor(-3));
+        assertEquals(Math.floor(-123.45), Floor.floor(-123.45));
+    }
+}
