搜索二维矩阵2 合并两个有序链表

240. 搜索二维矩阵 II - 力扣（LeetCode）

class Solution {
public:
    bool searchMatrix(vector<vector<int>>& matrix, int target) {
        int i = matrix.size() - 1, j = 0;
        while(i >= 0 && j < matrix[0].size())
        {
            if(matrix[i][j] > target) i--;
            else if(matrix[i][j] < target) j++;
            else return true;
        }
        return false;
    }
};

class Solution {
public:
    ListNode* mergeTwoLists(ListNode* list1, ListNode* list2) {
        ListNode* dum = new ListNode(0);
        ListNode* cur = dum;
        while (list1 != nullptr && list2 != nullptr) {
            if (list1->val < list2->val) {
                cur->next = list1;
                list1 = list1->next;
            }
            else {
                cur->next = list2;
                list2 = list2->next;
            }
            cur = cur->next;
        }
        cur->next = list1 != nullptr ? list1 : list2;
        return dum->next;
    }
};