题解 | #链表相加(二)#

/**
 * struct ListNode {
 *  int val;
 *  struct ListNode *next;
 *  ListNode(int x) : val(x), next(nullptr) {}
 * };
 */
class Solution {
  public:
    ListNode* addInList(ListNode* head1, ListNode* head2) {
        vector<int> v1;
        vector<int> v2;
        for (ListNode* cur = head1; cur; cur = cur->next) {
            v1.push_back(cur->val);
        }
        for (ListNode* cur = head2; cur; cur = cur->next) {
            v2.push_back(cur->val);
        }
        int i = v1.size() - 1;
        int j = v2.size() - 1;
        int jin = 0;
        ListNode* rethead = new ListNode(0);
        while (i >= 0 && j >= 0) {
            int temp = v1[i--] + v2[j--] + jin;
            jin = temp > 9 ? 1 : 0;
            temp %= 10;
            ListNode* cur = new ListNode(temp);
            cur->next = rethead->next;
            rethead->next = cur;
        }
        while (i >= 0) {
            int temp = v1[i--] + jin;
            jin = temp > 9 ? 1 : 0;
            temp %= 10;
            ListNode* cur = new ListNode(temp);
            cur->next = rethead->next;
            rethead->next = cur;
        }
        while (j >= 0) {
            int temp =  v2[j--] + jin;
            jin = temp > 9 ? 1 : 0;
            temp %= 10;
            ListNode* cur = new ListNode(temp);
            cur->next = rethead->next;
            rethead->next = cur;
        }
        if(jin==1){
            rethead->val = 1;
            return rethead;
        }else {
            return rethead->next;
        }
    }
};