HLine paintOn() method (lines
47,48)
for ( int i = 0; i < length; i++ ){ s.paintAt( x+i , y, paintChar ); }
Counts from i = 0 to i = length-1, executing whats in the body
each time
i=0: ask Screen s to put
paintChar at (x,y)
i=1: ask Screen s to put
paintChar at (x+1,y)
i=2: ask Screen s to put
paintChar at (x+2,y)
and so on
at
(x+length-1,y)