[Leetcode] Search a 2D Matrix

class Solution {public:    bool searchMatrix(vector<vector<int> > &matrix, int target) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        int i = 0;        int j = matrix[0].size() - 1;        while (i < matrix.size() && j >= 0)        {            if (matrix[i][j] > target)                --j;            else if (matrix[i][j] < target)                ++i;            else                return true;        }                return false;    }};