Create Add Two Numbers.cpp

Author: daizhenyang

Add Two Numbers.cpp

@@ -0,0 +1,62 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode(int x) : val(x), next(NULL) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode *addTwoNumbers(ListNode *l1, ListNode *l2) {
+        // Start typing your C/C++ solution below
+        // DO NOT write int main() function
+        ListNode *h=l1,*p1,*p2;
+        int carry=0;
+        while (l1&&l2)
+        {
+            l1->val=l1->val+l2->val+carry;
+            carry=l1->val>9;
+            l1->val%=10;
+            p1=l1;p2=l2;
+            l1=l1->next;
+            l2=l2->next;
+        }
+        if (!l1&&!l2&&carry)
+        {
+            p1->next=new ListNode(1);
+        }
+        if (l1)
+        {
+            while (l1)
+            {
+                l1->val=l1->val+carry;
+                carry=l1->val>9;
+                l1->val%=10;
+                p1=l1;
+                l1=l1->next;
+            }
+            if (carry)
+            {
+                p1->next=new ListNode(1);
+            }
+        }
+        else if (l2)
+        {
+            p1->next=l2;
+            while (l2)
+            {
+                l2->val=l2->val+carry;
+                carry=l2->val>9;
+                l2->val%=10;
+                p2=l2;
+                l2=l2->next;
+            }
+            if (carry)
+            {
+                p2->next=new ListNode(1);
+            }
+        }
+        return h;
+    }
+};