products and sums of arraylist

Author: faisalnjs

Array.java

@@ -1,3 +1,5 @@
+import java.util.ArrayList;
+
 public class Array {
     public static void changeElement(int n) {
         n += 3;
@@ -7,11 +9,65 @@ public static void changeArrayElement(int[] n) {
         n[0] += 3;
     }
 
+    public static int getProductSum(ArrayList<Integer> list, int[] arr) {
+        int fin = 0;
+        int index = 0;
+        for (int num : list) {
+            if (index < arr.length) {
+                fin += num * arr[index];
+                index++;
+            }
+        }
+        return fin;
+    }
+
+    public static int[] getProducts(ArrayList<Integer> list, int[] arr) {
+        int num = list.size();
+        if (list.size() < arr.length) {
+            num = arr.length;
+        }
+        int[] fin = new int[num];
+        int index = 0;
+        if (num == list.size()) {
+            for (int n : list) {
+                if (index < arr.length) {
+                    fin[index] = n * arr[index];
+                } else {
+                    fin[index] = arr[index];
+                }
+                index++;
+            }
+        } else {
+            for (int n : arr) {
+                if (index < list.size()) {
+                    fin[index] = n * list.get(index);
+                } else {
+                    fin[index] = list.get(index);
+                }
+                index++;
+            }
+        }
+        return fin;
+    }
+
     public static void main(String[] args) {
         int[] list = { 1, 2, 3, 4 };
         changeElement(list[0]);
         System.out.println(list[0]); // 1
         changeArrayElement(list);
         System.out.println(list[0]); // 4
+        ArrayList<Integer> list1 = new ArrayList<Integer>();
+        list1.add(2);
+        list1.add(1);
+        list1.add(4);
+        int[] arr = { 5, 0, 3 };
+        for (int product : getProducts(list1, arr))
+            System.out.println(product); // { 10, 0, 12 }
+        System.out.println(getProductSum(list1, arr)); // 22
+        ArrayList<Integer> list2 = new ArrayList<Integer>();
+        int[] arr2 = { 2, 3, 7 };
+        for (int product : getProducts(list2, arr2))
+            System.out.println(product); // { 10, 0, 12 }
+        System.out.println(getProductSum(list2, arr2)); // 22
     }
 }