If constant at layer i is even , beven is true , otherwise false . If the coefficient of x at layer i is even , aeven is true , otherwise false .
$ beven = true ; $ aeven = false ; $ n = 2 ; for ( $ i = 0 ; $ i < $ n ; $ i ++ ) { $ a = $ steps [ $ i ] [ 0 ] ; $ b = $ steps [ $ i ] [ 1 ] ;