class Solution {
public:
    vector<int> findElement(vector<vector<int> > mat, int n, int m, int x) {
        // write code here
        vector<int> res;
        int i = 0, j = m-1;
        while(i<n && j>=0){
            if(mat[i][j] == x){
                res.push_back(i);
                res.push_back(j);
                break;
            }
            else if(mat[i][j] < x){
                i++;
            }
            else{
                j--;
            }
        }
        return res;
    }
};