add 1352

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_1352.java

@@ -1,5 +1,8 @@
 package com.fishercoder.solutions;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * 1352. Product of the Last K Numbers
  *
@@ -37,18 +40,27 @@
  * */
 public class _1352 {
     public static class Solution1 {
+        /**credit: https://leetcode.com/problems/product-of-the-last-k-numbers/discuss/510260/JavaC%2B%2BPython-Prefix-Product*/
         public static class ProductOfNumbers {
 
-            public ProductOfNumbers() {
+            List<Integer> list;
 
+            public ProductOfNumbers() {
+                add(0);
             }
 
             public void add(int num) {
-
+                if (num > 0) {
+                    list.add(list.get(list.size() - 1) * num);
+                } else {
+                    list = new ArrayList<>();
+                    list.add(1);
+                }
             }
 
             public int getProduct(int k) {
-                return -1;
+                int size = list.size();
+                return k >= size ? 0 : (list.get(size - 1) / list.get(size - k - 1));
             }
         }
     }

src/test/java/com/fishercoder/_1352Test.java

@@ -1,20 +1,26 @@
 package com.fishercoder;
 
 import com.fishercoder.solutions._1352;
-import org.junit.BeforeClass;
 import org.junit.Test;
 
+import static org.junit.Assert.assertEquals;
+
 public class _1352Test {
     private static _1352.Solution1.ProductOfNumbers productOfNumbers;
 
-    @BeforeClass
-    public static void setup() {
-        productOfNumbers = new _1352.Solution1.ProductOfNumbers();
-    }
-
     @Test
     public void test1() {
-
+        productOfNumbers = new _1352.Solution1.ProductOfNumbers();
+        productOfNumbers.add(3);
+        productOfNumbers.add(0);
+        productOfNumbers.add(2);
+        productOfNumbers.add(5);
+        productOfNumbers.add(4);
+        assertEquals(20, productOfNumbers.getProduct(2));
+        assertEquals(40, productOfNumbers.getProduct(3));
+        assertEquals(0, productOfNumbers.getProduct(4));
+        productOfNumbers.add(8);
+        assertEquals(32, productOfNumbers.getProduct(2));
     }
 
 }