Kate drew a 33×33 checkered square (lattice) on the asphalt with white chalk (i. e. there are 34 horizontal segments and 34 vertical segments drawn). By one move it is allowed to pick out an arbitrary square (of any size) and repaint its boundary using chalk of blue color. In different moves, it is allowed to repaint any segment more than once. What is the smallest number of such moves required to repaint all the initial lines in blue color?