LeetCode 240. Search a 2D Matrix II

描述

解决

class Solution {
public:
bool searchMatrix(vector<vector<int>>& matrix, int target) {
int r_length = matrix.size();
int c_length = r_length ? matrix[0].size() : 0;
//cout << "matrix = " << r_length << " " << c_length << endl;
for (int i = 0; i < r_length; ++i)
{
bool flag = binary_search(matrix[i].begin(), matrix[i].end(), target);
if (flag)
return true;
}
return false;
}
};

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