Código Delphi [-]
Cost con: set of char =['A','a'];

Código Delphi [-]
 
unit unit1;
interface
uses
sysutils;
const
max=1024;
type
            CVectorS=class
             S: array[1..max] of string ;
             N: integer;
             constructor crear ;
             procedure dimencionar(dim:integer);
             procedure poner(posi:integer ; que:string);
             procedure mostrar(var s:cvectorS);
            
             function elemento(posi:integer):string;
             function dimencion:integer;
             end;

implementation

constructor CVectorS.crear;
begin
   N:=0;
end;
 
function CVectorS.dimencion: integer;
begin
  dimencion:=N
end;
procedure CVectorS.dimencionar(dim: integer);
begin
  N:=dim;
end;
function CVectorS.elemento(posi: integer): string;
begin
  elemento:=s[posi];
end;
 
procedure CVectorS.mostrar(var s: cvectorS);
var
  I: Integer;
begin
  for I := 1 to s.Dimencion do
  begin
    write(s.elemento(i):8);
  end;
end;
 
procedure CVectorS.poner(posi: integer; que: string);
begin
  s[posi]:=que;
end;
end.

Código Delphi [-]
var
  i, j, cc: Integer;
begin
  con:= 0;
  for i:= 1 to max do
   for j:= 1 to Length(S[i]) do
    if UpCase(S[i][j]) = 'A' then Inc(cc);
   // en la variable cc, tendrás la cantidad de apariciones de la letra 'A' o 'a'
   ...

Código Delphi [-]
var  i, j, cc: Integer;
begin  con:= 0;  
for i:= 1 to max do  
 for j:= 1 to Length(S[i]) do    
if UpCase(S[i][j]) = 'A' then Inc(cc); 
 // en la variable cc, tendrás la cantidad de apariciones de la letra 'A' o 'a'

Código Delphi [-]
var
  i,cc : Integer;
begin
  cc:= 0;
  for i:= 1 to Length(S) do
      if upCase(S[i]) = 'A' then
      cc:=cc+1;
     result:=cc;
end;

Código Delphi [-]
program Project2;
{$APPTYPE CONSOLE}
uses
  SysUtils;
const
  max = 5;
var
 i, j, cc: Integer;
 S: array[1..max] of string;
begin
  S[1]:= 'La';
  S[2]:= 'CasA';
  S[3]:= 'de la';
  S[4]:= 'Arboleda';
  S[5]:= 'tupidA';
  cc:= 0;
  for i:= 1 to max do
   for j:= 1 to Length(S[i]) do
    if UpCase(S[i][j]) = 'A' then Inc(cc);
  writeln(cc);
  readln;
end.

Código Delphi [-]
var
  i,cc : Integer;
begin
  cc:= 0;
  for i:= 1 to Length(S) do
      if upCase(S[i]) = 'A' then
      cc:=cc+1;
     result:=cc;
end;