program MissingAlphabet;
type
TStringArray = array[1..26] of char;
procedure GetMissingAlphabetChars(Input: string; var Missing: TStringArray; var Count: Integer);
var
Present: set of char;
C: char;
I: Integer;
begin
Present := [];
{ Normalize input: lowercase + keep only a..z }
for I := 1 to Length(Input) do
begin
C := Input[I];
if (C >= 'A') and (C <= 'Z') then
C := Chr(Ord(C) + 32); { convert to lowercase }
if (C >= 'a') and (C <= 'z') then
Include(Present, C);
end;
{ Collect missing letters }
Count := 0;
for C := 'a' to 'z' do
if not (C in Present) then
begin
Inc(Count);
Missing[Count] := C;
end;
end;
var
Missing: TStringArray;
Count, I: Integer;
begin
GetMissingAlphabetChars('PHP Programming', Missing, Count);
for I := 1 to Count do
WriteLn(Missing[I]);
end.
(*
run:
b
c
d
e
f
j
k
l
q
s
t
u
v
w
x
y
z
*)