class Solution {public: int shipWithinDays(vector<int>& weights, int days) { int l=*max_element(weights.begin(),weights.end());

分析有题意可知，将矩阵按行排列可化为一个有序数列，可采用二分来寻找目标值，其中中间值的下标为matrix[mid/n][mid%n],n为列数。class Solution {public: bool searchMatrix(vector<vector<int>>&a