question: public void add ( double x , double y ) { if ( len == data . length ) { data = Arrays . copyOf ( data , len << 1 ) ; } data [ len ++ ] = x ; data [ len ++ ] = y ; minx = Math . min ( minx , x ) ; maxx = Math . max ( maxx , x ) ; miny = Math . min ( miny , y ) ; maxy = Math . max ( maxy , y ) ; }
target:  Add a coordinate pair, but don't simplify