I need expert advisor

i need to convert the attached indicator to expert 

#property indicator_separate_window
#property indicator_buffers 2
#property indicator_color1 Green
#property indicator_color2 Red
#property indicator_width1 5
#property indicator_width2 5

#property indicator_minimum 0

extern int MA_1_Bars = 20;
extern int MA_2_Bars = 5;

double up[];
double down[];
double MA_1[];
double MA_2[];

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
//---- indicators buffer used in calculation
   IndicatorBuffers(4);
   SetIndexBuffer(0,up);
   SetIndexBuffer(1,down);
   SetIndexBuffer(2,MA_1);
   SetIndexBuffer(3,MA_2);
  
  
//----indicator drawing style
   SetIndexStyle(0,DRAW_HISTOGRAM);
   SetIndexStyle(1,DRAW_HISTOGRAM);
  
  
//----Data window & Index Label  
   SetIndexLabel(0,"up");
   SetIndexLabel(1,"down");
  
   
//----indicator begin & digit number used at calculation
    SetIndexDrawBegin(0,1);
    IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));
      
//----
   return(0);
  }
 
  //+------------------------------------------------------------------+
//| Custom indicator deinitialization function                       |
//+------------------------------------------------------------------+
int deinit()
  {
//----
  
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int start()
  {
   int   limit;
   int    counted_bars=IndicatorCounted();
  
//---- check for errors
  if(counted_bars<0) return(-1);
 
//---- recount the last Bar
  if(counted_bars>0) counted_bars--;
  limit=Bars-counted_bars;
 
//--- main loop

  for(int  ii=0; ii<limit;ii++)
  MA_1[ii] = iMA(NULL,0,MA_1_Bars,0,MODE_LWMA,PRICE_CLOSE,ii);
 
 
  for(int  i=0; i<limit;i++)
  MA_2[i] =  iMAOnArray(MA_1,0,MA_2_Bars,0,MODE_LWMA,i);
 
  for(int  y=0; y<limit;y++)
  if(MA_1[y] >  MA_2[y])
  up[y] = 1;
  else
  if(MA_1[y] <  MA_2[y])
  down[y] = 1;
 
 
   
                                                          


//----
   return(0);
  }
//+------------------------------------------------------------------+