Given a matrix of size √ n×√ n with every entry being a 0 or a 1, the leftmost-one problem asks to determine the position of the leftmost 1, if any, in each row of the matrix. The leftmost-one problem finds applications in image processing, digitized geometry and computer graphics, among others. Recently, an O( n 1 6 ) time solution to the leftmost-one problem on a mesh with row buses has been proposed. However, the computational model assumes that processors have unbounded memory. We show that the problem can be solved in O( n 1 6 ) time on a √ n×√ n mesh with row broadcasting, even if each processor has only a constant number of registers.