Add pollard rho algorithm (#3260)

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

@@ -0,0 +1,51 @@
+package com.thealgorithms.maths;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+class PollardRhoTest {
+
+	@Test
+	void testPollardRhoForNumber315MustReturn5() {
+		//given
+		int number = 315;
+		int expectedResult = 5;
+
+		//when
+		int actualResult = PollardRho.pollardRho(number);
+
+		//then
+		assertEquals(expectedResult, actualResult);
+	}
+
+	@Test
+	void testPollardRhoForNumber187MustReturn11() {
+		//given
+		int number = 187;
+		int expectedResult = 11;
+
+		//when
+		int actualResult = PollardRho.pollardRho(number);
+
+		//then
+		assertEquals(expectedResult, actualResult);
+	}
+
+	@Test
+	void testPollardRhoForNumber239MustThrowException() {
+		//given
+		int number = 239;
+		String expectedMessage = "GCD cannot be found.";
+
+		//when
+		Exception exception = assertThrows(RuntimeException.class, () -> {
+			PollardRho.pollardRho(number);
+		});
+		String actualMessage = exception.getMessage();
+
+		//then
+		assertEquals(expectedMessage, actualMessage);
+	}
+}