get the range of price from the given quantity of bars in metatrader 4

mql Get Current Range.mq4

// Gets the range (highest minus lowest) of price for the last 5 bars
// double currentRange = CalculateCurrentRange(5);

double CalculateCurrentRange(int howManyBars){
   double   highVal;
   double   lowVal;
   
   int highVal_index=iHighest(NULL,0,MODE_HIGH,howManyBars,0);
   int lowVal_index=iLowest(NULL,0,MODE_LOW,howManyBars,0);
   
   if(highVal_index!=-1 && lowVal_index!=-1) {
      highVal=High[highVal_index];
      lowVal=Low[lowVal_index];
      return NormalizeDouble(highVal - lowVal,Digits);
   } else {
      return 0;
   }
}