[feat] Added AddTwoNumberLinkedLists solution

Author: ravivats

platform-problems/leetcode/leetcode-problems/P02AddTwoNumberLinkedLists.java

@@ -0,0 +1,64 @@
+/**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode() {}
+ *     ListNode(int val) { this.val = val; }
+ *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
+ * }
+ */
+
+/**
+ * Input: l1 = [2,4,3], l2 = [5,6,4]
+ * Output: [7,0,8]
+ * Explanation: 342 + 465 = 807.
+ */
+
+/**
+ * Input: l1 = [9,9,9,9,9,9,9], l2 = [9,9,9,9] Output: [8,9,9,9,0,0,0,1]
+ */
+
+class Solution {
+    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
+        ListNode resultList = new ListNode();
+        ListNode root = resultList;
+        int carryOver = 0;
+        int sum = 0;
+        while (l1 != null && l2 != null) {
+            sum = (l1.val + l2.val + carryOver) % 10;
+            carryOver = (l1.val + l2.val + carryOver) / 10;
+            ListNode temp = new ListNode(sum);
+            root.next = temp;
+            root = root.next;
+            l1 = l1.next;
+            l2 = l2.next;
+        }
+
+        while (l1 != null) {
+            sum = (l1.val + carryOver) % 10;
+            carryOver = (l1.val + carryOver) / 10;
+            ListNode temp = new ListNode(sum);
+            root.next = temp;
+            root = root.next;
+            l1 = l1.next;
+        }
+
+        while (l2 != null) {
+            sum = (l2.val + carryOver) % 10;
+            carryOver = (l2.val + carryOver) / 10;
+            ListNode temp = new ListNode(sum);
+            root.next = temp;
+            root = root.next;
+            l2 = l2.next;
+        }
+
+        if (carryOver > 0) {
+            ListNode temp = new ListNode(carryOver);
+            root.next = temp;
+            root = root.next;
+        }
+
+        return resultList.next;
+    }
+}

platform-problems/leetcode/may-2020-leetcoding-challenge/leetcode_18_permutation_as_substring/Solution.java

@@ -22,7 +22,7 @@ public boolean checkAllValues(HashMap<Character, Integer> map, char[] arr, int i
     }
 
     public boolean checkInclusion(String s1, String s2) {
-        HashMap<Character,Integer> charMap = new HashMap<Character, Integer>();
+        HashMap<Character,Integer> charMap = new HashMap<>();
         for (char c : s1.toCharArray()) {
             if (charMap.containsKey(c)) {
                 int value = charMap.get(c);
@@ -35,7 +35,7 @@ public boolean checkInclusion(String s1, String s2) {
         char[] arr = s2.toCharArray();
         for (int i = 0; i < arr.length; i++) {
             if (charMap.containsKey(arr[i])) {
-                HashMap<Character, Integer> cloneCharMap = (HashMap)charMap.clone();
+                HashMap<Character, Integer> cloneCharMap = (HashMap<Character,Integer>)charMap.clone();
                 if (checkAllValues(cloneCharMap, arr, i)) {
                     return true;
                 };