How to make the program work without copy, i.e. without procedures and functions in pascal abc.net?

Question

Pascal

Hello. Need help with a task. Given text. Delete all words that start with the same letter.
How to make the program work without copy, i.e. without procedures and functions in pascal abc?
Here is the source code:

Program p1;
const
C = [' ', ',', '.'];
var
s,max_word: string;
i,k, prev: integer;
step: boolean;
begin
Write('Введите строку s=');
Read(s);
s:=s + ' ';
prev:=0;
for step:=false to true do
for i:=1 to length(s) do
begin
if s[i] in C then
begin
if i-prev>1 then
begin
if not step then 
begin
if i - prev - 1 > length(max_word) then
max_word := copy(s, prev + 1, i - prev - 1);
end
else 
if s[i - 1] = max_word[length(max_word)] then
write(copy(s, prev + 1, i - prev - 1), ' ');
end;
prev := i;
end;
end;
writeln;
end.