/*[[
	Name := AO
	Author := Copyright © 2003, MetaQuotes Software Corp.
	Link := http://www.metaquotes.ru/
	Separate Window := Yes
	First Color := LimeGreen
	First Draw Type := Histogram
	Use Second Data := Yes
	Second Color := Red
	Second Draw Type := Histogram
]]*/
Inputs : FastMAPeriod(13), SlowMAPeriod(34),SignalMAPeriod(13),shift(0);
Variables : cnt(0), sum(0), loopbegin(0), first(True), prevbars(0);
Variables : OsMA1(0), OsMA2(0),P(0), P2(0),prevP(0);

SetLoopCount(0);
// initial checkings
If FastMAPeriod < 1 Or SlowMAPeriod < 1 Then Exit;
If FastMAPeriod >= SlowMAPeriod Then Exit;
// check for additional bars loading or total reloading
If Bars < prevbars Or Bars-prevbars>1 Then first = True;
prevbars = Bars;
// loopbegin prevent counting of counted bars exclude current
If first Then Begin
loopbegin = Bars-SlowMAPeriod-1;
If loopbegin < 0 Then Exit; // not enough bars for counting
first = False; // this block is to be evaluated once only
End;

// convergence-divergence
loopbegin = loopbegin+1; // current bar is to be recounted too
For shift = loopbegin Downto 0 Begin
OsMA1 = iOsMA(FastMAPeriod,SlowMAPeriod,SignalMAPeriod,PRICE_CLOSE,shift);
//We need to do it again with a shift back one bar(shift+1)
//so we can change colors in the histogram.
OsMA2 = iOsMA(FastMAPeriod,SlowMAPeriod,SignalMAPeriod,PRICE_CLOSE,shift+1);

P = OsMA1;
P2 =OsMA2;

//If the current bar is less than the last bar in our histogram we want it to be Red.
//If the current bar is greater than the last bar in our histogram we want it to be Green.
If P>P2 then SetIndexValue(Shift,P);
If P2>P then SetIndexValue2(Shift,P2);

loopbegin = loopbegin-1; // prevent to previous bars recounting
End;