CCI ZERO CROSS WITH ALERT for Amibroker (AFL)

error in formula

You must use semicolon ; after buy and sell rule.

CAN ANY BODY CORRECT THIS FORMULA

Buy=CCI(20)>0;
Sell=CCI(20)<0;
Buy=ExRem(Buy, Sell);
Sell=ExRem(Sell, Buy);

Plot(CCI(20), "CCI", colorBlack, styleHistogram);
PlotShapes(IIf(Buy,shapeUpArrow,shapeNone) ,colorBrightGreen);
PlotShapes(IIf(Sell,shapeDownArrow,shapeNone),colorRed);