câu 1:

a) 

Var s: string;

Begin

   Write('nhap xau: '); readln(s);

   While pos(' ', s)<>0 do

        Delete(s, pos(' ', s), 1);

   Write(s);

   Readln

End.

b) 

Var s: string;

       i: byte;

Begin

   Write('nhap xau: '); readln(s);

   For i:=1 to length(s) do

      If s[i] in ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'] then write(s[i]);

   Readln

End.

 câu 2:

a) 

Var f: text;

       a, b: integer;

Begin

    Assign(f, 'BAI2.INP'); reset(f);

    Read(f, a, b); close(f);

    Write(a+b);

    Readln

End.

b)

Var f: text;

       a, b: integer;

Begin

    Assign(f, 'BAI2.OUT'); rewrite(f);

    Write('nhap a va b: '); readln(a, b);

    Write(f, a+b); close(f);

End. 

câu 3:

a) 

Procedure tong;

  Begin

       S := a + b;

  End;

b)

Function tong(x, y: integer): longint;

  Begin

       Tong := x + y;

  End;

câu 1:

a)

uses crt;

var s: string;

begin

clrscr;

write('nhap xau: '); readln(s);

while pos(' ', s)<>0 do

delete(s, pos(' ', s), 1);

write(s);

readln;

end.

b)

uses crt;

var s: string;

i: byte;

begin

clrscr;

write('nhap xau: '); readln(s);

for i:=1 to length(s) do

if s[i] in ['0'..'9'] then write(s[i]);

readln

end.

câu 2:

a) 

uses crt;

var f: text;

       a,b: integer;

begin

clrscr;

assign(f, 'BAI2.INP'); reset(f);

read(f, a, b);

close(f);

write(a+b);

readln;

end.

b)

uses crt;

var f: text;

a, b: integer;

begin

assign(f, 'BAI2.OUT'); rewrite(f);

write('nhap a va b: '); readln(a, b);

write(f, a+b);

close(f);

end.