How can carect this code

shift1 = 4;
shift2 = -4;
a= MA( Ref(Close,4), 10 );
b= MA( Ref(Close,-4), 10 );
x=MA( Close, 10 );
PH = Ref(High,-1); 
PL = Ref(Low,-1);

Plot(a, "MA-10", colorRed, styledashed );
Plot( b, "MA-shift", colorRed, styleThick, Null, Null, shift2);
Plot( MA( Close, 10 ), "MA+shift", colorGreen, styleThick, Null, Null, shift1); 
//Buy =Cover=   Cross( Close, EMA(Close, 10) ) AND C < Ref(C,4);  
//Sell =Short=  Cross( EMA(Close, 10), Close)  AND C  > Ref(C,4);

Buy =Cover=    Cross(a,b)  ;
Sell =Short=   Cross(b,a) ;

Color=IIf(BarsSince(Buy OR Cover)<BarsSince( Sell OR Short),ParamColor("Bullish",colorBrightGreen),ParamColor("Bearish",colorRed));
Plot(C,"Ganesh Tradlink ",Color,64);

PlotShapes(IIf(Buy==1, shapeUpArrow , shapeNone), colorGreen, 0,Low, Offset=-15);
PlotShapes(IIf(Sell==1, shapeDownArrow, shapeNone), colorRed, 0,High, Offset=-15);
PlotShapes(IIf(Short==1, shapehollowDownArrow, shapeNone), colorRed, 0,High, Offset=-25);
PlotShapes(IIf(cover==1, shapehollowUpArrow , shapeNone), colorGreen, 0,Low, Offset=-25);

You haven't told us anything about what you're trying to achieve, what you've tried, and why you think the code doesn't work.

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