Williams_Accumulation_Distribution

//+------------------------------------------------------------------+
//|                          Williams' Accumulation/Distribution.mq4 |
//|                      Copyright © 2007, MetaQuotes Software Corp. |
//|                                        http://www.metaquotes.net |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2007, MetaQuotes Software Corp."
#property link      "http://www.metaquotes.net"
//----
#property indicator_separate_window
#property indicator_buffers 1
#property indicator_color1 LightSeaGreen
//---- buffers
double ExtMapBuffer1[];
//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
   IndicatorShortName("W_A/D");
//---- indicators
   SetIndexStyle(0, DRAW_LINE);
   SetIndexBuffer(0, ExtMapBuffer1);
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator deinitialization function                       |
//+------------------------------------------------------------------+
int deinit()
  {
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int start()
  {
   double AD, TRH, TRL;
   int  i, counted_bars = IndicatorCounted();
//----
   i = Bars - counted_bars - 1;
   while(i >= 0)
     {
       TRH = MathMax(High[i], Close[i+1]);
       TRL = MathMin(Low[i], Close[i+1]);
       if(Close[i] > Close[i+1] + Point)
           AD = Close[i] - TRL;
       else 
           if(Close[i] < Close[i+1] - Point)   
               AD = Close[i] - TRH;
           else 
               AD = 0;
       ExtMapBuffer1[i] = ExtMapBuffer1[i+1] + AD;
       i--;
     }
//----
   return(0);
  }
//+------------------------------------------------------------------+