package com.thealgorithms.maths; import static org.junit.jupiter.api.Assertions.assertEquals; import static org.junit.jupiter.api.Assertions.assertThrows; import java.util.HashMap; import org.junit.jupiter.api.Test; public class ReverseNumberTest { @Test public void testReverseNumber() { HashMap testCases = new HashMap<>(); testCases.put(0, 0); testCases.put(1, 1); testCases.put(10, 1); testCases.put(123, 321); testCases.put(7890, 987); for (final var tc : testCases.entrySet()) { assertEquals(ReverseNumber.reverseNumber(tc.getKey()), tc.getValue()); } } @Test public void testReverseNumberThrowsExceptionForNegativeInput() { assertThrows(IllegalArgumentException.class, () -> ReverseNumber.reverseNumber(-1)); } }