LeetCode 240. 搜索二维矩阵 II Search a 2D Matrix II (Medium)

class Solution {
public:
    bool searchMatrix(vector<vector<int>>& matrix, int target) {
        
        if (matrix.empty()) return false;

        int rows = matrix.size();
        int cols = matrix[0].size();

        //主要思路：从右上角数开始对比，如小于右上角数则列数-1，如大于则行数-1
        int cur_row = 0;
        int cur_col = cols - 1;
        while (cur_row < rows && cur_col >= 0)
        {
            if (matrix[cur_row][cur_col] == target)
                return true;
            else if (matrix[cur_row][cur_col] > target)
                --cur_col;
            else
                ++cur_row;
        }
        return false;
    }
};