WineProblemTest.java

packagecom.thealgorithms.dynamicprogramming;

importstaticorg.junit.jupiter.api.Assertions.assertEquals;
importstaticorg.junit.jupiter.api.Assertions.assertThrows;

importorg.junit.jupiter.api.Test;

/**
 * Unit tests for the WineProblem class.
 * This test class verifies the correctness of the wine selling problem solutions.
 */
classWineProblemTest {

/**
 * Test for wpRecursion method.
 */
@Test
voidtestWpRecursion() {
int[] wines = {2, 3, 5, 1, 4}; // Prices of wines
intexpectedProfit = 50; // The expected maximum profit
assertEquals(expectedProfit, WineProblem.wpRecursion(wines, 0, wines.length - 1), "The maximum profit using recursion should be 50.");
 }

/**
 * Test for wptd method (Top-Down DP with Memoization).
 */
@Test
voidtestWptd() {
int[] wines = {2, 3, 5, 1, 4}; // Prices of wines
intexpectedProfit = 50; // The expected maximum profit
assertEquals(expectedProfit, WineProblem.wptd(wines, 0, wines.length - 1, newint[wines.length][wines.length]), "The maximum profit using top-down DP should be 50.");
 }

/**
 * Test for wpbu method (Bottom-Up DP with Tabulation).
 */
@Test
voidtestWpbu() {
int[] wines = {2, 3, 5, 1, 4}; // Prices of wines
intexpectedProfit = 50; // The expected maximum profit
assertEquals(expectedProfit, WineProblem.wpbu(wines), "The maximum profit using bottom-up DP should be 50.");
 }

/**
 * Test with a single wine.
 */
@Test
voidtestSingleWine() {
int[] wines = {10}; // Only one wine
intexpectedProfit = 10; // Selling the only wine at year 1
assertEquals(expectedProfit, WineProblem.wpbu(wines), "The maximum profit for a single wine should be 10.");
 }

/**
 * Test with multiple wines of the same price.
 */
@Test
voidtestSamePriceWines() {
int[] wines = {5, 5, 5}; // All wines have the same price
intexpectedProfit = 30; // Profit is 5 * (1 + 2 + 3)
assertEquals(expectedProfit, WineProblem.wpbu(wines), "The maximum profit with same price wines should be 30.");
 }

/**
 * Test with no wines.
 */
@Test
voidtestNoWines() {
int[] wines = {};
assertThrows(IllegalArgumentException.class, () -> WineProblem.wpbu(wines), "The maximum profit for no wines should throw an IllegalArgumentException.");
 }
}