Feat:add 0/1knapsack and 0/1knapsacktabulation along with their tests

TheAlgorithms · alxkm · Jul 22, 2025 · Jul 20, 2025 · Jul 20, 2025 · Jul 20, 2025
commit 72ce8a257bc313f1d5e4753c4108d34e24168469
@@ -1,6 +1,7 @@
 package com.thealgorithms.dynamicprogramming;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import org.junit.jupiter.api.Test;
 
@@ -37,4 +38,41 @@ public void zeroCapacity() {
 
         assertEquals(0, KnapsackZeroOneTabulation.compute(values, weights, capacity, itemCount));
     }
+
+    @Test
+    public void negativeCapacity() {
+        int[] values = {10, 20, 30};
+        int[] weights = {1, 1, 1};
+        int capacity = -10;
+        int itemCount = values.length;
+
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> KnapsackZeroOneTabulation.compute(values, weights, capacity, itemCount));
+        assertEquals("Capacity must not be negative.", exception.getMessage());
+    }
+
+    @Test
+    public void mismatchedLengths() {
+        int[] values = {60, 100}; // Only 2 values
+        int[] weights = {10, 20, 30}; // 3 weights
+        int capacity = 50;
+        int itemCount = 2; // Matches `values.length`
+
+        // You could either expect 0 or throw an IllegalArgumentException in your compute function
+        assertThrows(IllegalArgumentException.class, () -> { KnapsackZeroOneTabulation.compute(values, weights, capacity, itemCount); });
+    }
+
+    @Test
+    public void nullInputs() {
+        int[] weights = {1, 2, 3};
+        int capacity = 10;
+        int itemCount = 3;
+
+        IllegalArgumentException exception1 = assertThrows(IllegalArgumentException.class, () -> KnapsackZeroOneTabulation.compute(null, weights, capacity, itemCount));
+        assertEquals("Values and weights arrays must not be null.", exception1.getMessage());
+
+        int[] values = {1, 2, 3};
+
+        IllegalArgumentException exception2 = assertThrows(IllegalArgumentException.class, () -> KnapsackZeroOneTabulation.compute(values, null, capacity, itemCount));
+        assertEquals("Values and weights arrays must not be null.", exception2.getMessage());
+    }
 }