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using namespace std;
class Solution {
public:
    bool searchMatrix(vector<vector<int>> &matrix, int target) {
        // IMPORTANT: Please reset any member data you declared, as
        // the same Solution instance will be reused for each test case.
        if(matrix.size() <= 0)
            return false;
        if(target > matrix[matrix.size()-1][matrix[0].size()-1])
            return false;
        vector<int>cols(matrix.size());
        for(int i = 0; i < matrix.size(); i++) {
            cols[i] = matrix[i][matrix[0].size()-1];
        }
        int colindex = bsearch(0, (int)(matrix.size()), cols, target);
        if(colindex == -1)
            return true;
        int rowindex = bsearch(0, (int)(matrix[colindex].size()), matrix[colindex], target);
        if(rowindex == -1)
            return true;
        return false;
    }
    int bsearch(int left, int right, vector<int> seq, int target) {
        if(left > right) {
            return right + 1;
        }
        int mid = (left + right) / 2;
        if(seq[mid] == target) {
            return -1;
        } else if(seq[mid] < target) {
            return bsearch(mid+1, right, seq, target);
        } else {
            return bsearch(left, mid-1, seq, target);
        }
    }
};