public class Solution {
  public int[] search(int[][] matrix, int target) {
    // Write your solution here.
    if (matrix.length == 0 || matrix[0].length == 0) {
      return new int[] {-1, -1};
    }
    int rows = matrix.length;
    int cols = matrix[0].length;
    int left = 0;
    int right = rows * cols - 1;
    while (left <= right) {
      int mid = left + (right - left) / 2;
      int row = mid / cols;
      int col = mid % cols;
      if ( matrix[row][col] == target) {
        return new int[] {row, col};
      } else if (matrix[row][col] < target) {
        left = mid + 1;
      } else {
        right = mid - 1;
      }
    }
    return new int[] {-1, -1};
  }
}

log(col * row)