Procedures and Functions  107  1. The second fonn of the  procedure heading,  i.e., one with a  parameter list.  2.  Formal Parameters.  The  parameter list  gives the name of each  fonnal parameter followed by its type.  MinMax  has  L, Min,  and  Max  as fonnal parameters.  The fonnal  parameter list  opens a new scope for the parameters.  3.  Actual Parameters.  Note  a correspondence  between  the  procedure heading and the procedure statement. The latter  contains a list of  actual parameters,  which are substituted for  the corresponding fonnal parameters that are defined in the  program MinMax3(Input,Output);  { Program 11.2 - Modify Program 11.1 for two lists.  }  const  MaxSize = 20;  type  ListSize = 1 .. MaxSize;  List = array  [ListSize]  of Integer;  var  Item:  ListSize;  A,  B:  List;  MinA,  MinB,  MaxA,  MaxB:  Integer;  procedure MinMax(var L:  List; var Min,  Max:  Integer);  var  Item:  ListSize;  First,  Second:  Integer;  begin  Min  := L[l];  Max:= Min;  Item:= 2;  while Item < MaxSize do begin  First := L[Item];  Second:= L[Item+1];  if First > Second then begin  if First> Max  then Max  := First;  if Second < Min then Min  Second  end else begin  if Second> Max  then Max  .- Second;  if First < Min then Min  := First  end;  Item .= Item + 2  end;  if Item = MaxSize then  if L[MaxSize]  > Max  then Max  else  L[MaxSize] 