Need pivot line .. code help

Friends ... Below code ll plot Line for High and Low values of candle which i click ..

Plot(C,"",colorWhite,styleCandle);
selectH = SelectedValue( H );
selectL = SelectedValue( L );
Plot( selectH, "", colorLime,styleDots);
Plot( selectL, "", colorRed,styleDots);


i need pivot line to be plotted between high and low line ..

Plz help me ..