力扣240.搜索二维矩阵II-C++解决方案详细解析

class Solution {
public:
    bool searchMatrix(vector<vector<int>>& matrix, int target) {
        // 从右上角开始遍历，每次只能往左或往下
        int m = matrix.size(), n = matrix[0].size();
        int i = 0, j = n - 1;

        while (i < m && j >= 0) {
            if (matrix[i][j] > target) {
                --j;
            }
            else if (matrix[i][j] < target){
                ++i;
            }
            else {
                return true;
            }
        }

        return false;
    }
};