Merge pull request #80 from gantavya123/patch-2

Create add-two-numbers.cpp

Author: gantavyamalviya

CPP/Problems/add-two-numbers.cpp

@@ -0,0 +1,47 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ * int val;
+ * ListNode *next;
+ * ListNode() : val(0), next(nullptr) {}
+ * ListNode(int x) : val(x), next(nullptr) {}
+ * ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+ ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
+ ListNode* dummy = new ListNode(0);
+ ListNode* ll = dummy;
+ int carry = 0;
+ int sum = 0;
+ while(l1 and l2){
+ sum = l1->val + l2->val + carry;
+ ll->next = new ListNode(sum%10);
+ ll = ll->next;
+ carry = sum/10;
+ l1 = l1->next;
+ l2 = l2->next;
+ }
+ while(l1){
+ sum = l1->val + carry;
+ ll->next = new ListNode(sum%10);
+ ll = ll->next;
+ carry = sum/10;
+ l1 = l1->next;
+ 
+ }
+ while(l2){
+ sum = l2->val + carry;
+ ll->next = new ListNode(sum%10);
+ ll = ll->next;
+ carry = sum/10;
+ l2 = l2->next;
+ }
+ if(carry != 0){
+ ll->next = new ListNode(carry);
+ ll = ll->next;
+ }
+ return dummy->next;
+ }
+};