From 68dd2e91976793fda490fdc117df070f948a517e Mon Sep 17 00:00:00 2001 From: Albina Gimaletdinova Date: Thu, 27 Jul 2023 17:57:15 +0300 Subject: [PATCH 1/3] Factorial refactoring, added unit tests --- .../java/com/thealgorithms/maths/Factorial.java | 16 ++++------------ .../com/thealgorithms/maths/FactorialTest.java | 12 +++++++++++- 2 files changed, 15 insertions(+), 13 deletions(-) diff --git a/src/main/java/com/thealgorithms/maths/Factorial.java b/src/main/java/com/thealgorithms/maths/Factorial.java index 90fcde543a4d..e8b3f1a4e54f 100644 --- a/src/main/java/com/thealgorithms/maths/Factorial.java +++ b/src/main/java/com/thealgorithms/maths/Factorial.java @@ -1,15 +1,6 @@ package com.thealgorithms.maths; public class Factorial { - - /* Driver Code */ - public static void main(String[] args) { - assert factorial(0) == 1; - assert factorial(1) == 1; - assert factorial(5) == 120; - assert factorial(10) == 3628800; - } - /** * Calculate factorial N using iteration * @@ -18,11 +9,12 @@ public static void main(String[] args) { */ public static long factorial(int n) { if (n < 0) { - throw new IllegalArgumentException("number is negative"); + throw new IllegalArgumentException("Input number cannot be negative!"); } long factorial = 1; - for (int i = 1; i <= n; factorial *= i, ++i) - ; + for (int i = 1; i <= n; ++i) { + factorial *= i; + } return factorial; } } diff --git a/src/test/java/com/thealgorithms/maths/FactorialTest.java b/src/test/java/com/thealgorithms/maths/FactorialTest.java index 752cd7a75cde..c07d67ed1b06 100644 --- a/src/test/java/com/thealgorithms/maths/FactorialTest.java +++ b/src/test/java/com/thealgorithms/maths/FactorialTest.java @@ -5,9 +5,19 @@ import org.junit.jupiter.api.Test; public class FactorialTest { + private static final String EXCEPTION_MESSAGE = "Input number cannot be negative!"; @Test - public void test() { + public void testWhenInvalidInoutProvidedShouldThrowException() { + IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> Factorial.factorial(-1)); + assertEquals(exception.getMessage(), EXCEPTION_MESSAGE); + } + + @Test + public void testCorrectFactorialCalculation() { + assertEquals(1, Factorial.factorial(0)); + assertEquals(1, Factorial.factorial(1)); assertEquals(120, Factorial.factorial(5)); + assertEquals(3628800, Factorial.factorial(10)); } } From 55ee441d832df1e20ab42ab7f6b3f5aa182a74d8 Mon Sep 17 00:00:00 2001 From: Albina Gimaletdinova Date: Fri, 28 Jul 2023 13:16:09 +0300 Subject: [PATCH 2/3] minor fix Co-authored-by: Andrii Siriak --- src/test/java/com/thealgorithms/maths/FactorialTest.java | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/test/java/com/thealgorithms/maths/FactorialTest.java b/src/test/java/com/thealgorithms/maths/FactorialTest.java index c07d67ed1b06..b22ad535a234 100644 --- a/src/test/java/com/thealgorithms/maths/FactorialTest.java +++ b/src/test/java/com/thealgorithms/maths/FactorialTest.java @@ -5,7 +5,7 @@ import org.junit.jupiter.api.Test; public class FactorialTest { - private static final String EXCEPTION_MESSAGE = "Input number cannot be negative!"; + private static final String EXCEPTION_MESSAGE = "Input number cannot be negative"; @Test public void testWhenInvalidInoutProvidedShouldThrowException() { From cc8efbbe0d3754708a4abeb187514dac22c4574e Mon Sep 17 00:00:00 2001 From: Albina Gimaletdinova Date: Fri, 28 Jul 2023 13:16:18 +0300 Subject: [PATCH 3/3] minor fix Co-authored-by: Andrii Siriak --- src/main/java/com/thealgorithms/maths/Factorial.java | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/main/java/com/thealgorithms/maths/Factorial.java b/src/main/java/com/thealgorithms/maths/Factorial.java index e8b3f1a4e54f..063f00bda507 100644 --- a/src/main/java/com/thealgorithms/maths/Factorial.java +++ b/src/main/java/com/thealgorithms/maths/Factorial.java @@ -9,7 +9,7 @@ public class Factorial { */ public static long factorial(int n) { if (n < 0) { - throw new IllegalArgumentException("Input number cannot be negative!"); + throw new IllegalArgumentException("Input number cannot be negative"); } long factorial = 1; for (int i = 1; i <= n; ++i) {