题目：搜索二维矩阵

方法1：

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