GCD done!

Interesting. The original code was like this:
	public static int getGCD(int a, int b) {
		if (b == 0) {
			return a;
		}

		if (b > a) {
			return getGCD(b, b % a);
		} else {
			return getGCD(b, a % b);
		}
	}
And it failed the test of 14159572, 63967072. After chaning the code to:
	public static int getGCD(int a, int b) {
		if (b == 0) {
			return a;
		}

		if (b > a) {
			return getGCD(b, a);
		} else {
			return getGCD(b, a % b);
		}
	}
It worked! I guess it's important to do a pretty exhaustive testing to
find this subtle bug

1 files changed, 33 insertions, 0 deletions

diff --git a/AlgoDesignAndTechniqueEdxJava/tests/GCDTest.java b/AlgoDesignAndTechniqueEdxJava/tests/GCDTest.java
new file mode 100644
index 0000000..1c8fedd
--- /dev/null
+++ b/AlgoDesignAndTechniqueEdxJava/tests/GCDTest.java
@@ -0,0 +1,33 @@
+import static org.junit.jupiter.api.Assertions.*;
+import org.junit.jupiter.api.Test;
+
+public class GCDTest {
+	@Test
+	void testGCD1() {
+		assertEquals(1, GCD.getGCD(18, 35));
+	}
+	@Test
+	void testGCD2() {
+		assertEquals(17657, GCD.getGCD(28851538, 1183019));
+	}
+
+	@Test
+	void testGCD3() {
+		assertEquals(7, GCD.getGCD(1344, 217));
+	}
+
+	@Test
+	void testGCD4() {
+		assertEquals(1344, GCD.getGCD(1344, 1344));
+	}
+
+	@Test
+	void testGCD5() {
+		assertEquals(4, GCD.getGCD(14159572, 63967072));
+	}
+
+	@Test
+	void testGCD6() {
+		assertEquals(4, GCD.getGCD(63967072,14159572));
+	}
+}